I have an 8 membered array which has to be defined conditionally. ie, for each condition, the values of the elements of the array will be different.
However, for each condition, I'd rather not define the elements one by one. Is there any way where I can define all the elements of the array together like this:
double c[8];
if ( a == p ){
c[]={values} ;
} else if ( a == q) {
c[]={values} ;
} else if (.. ){
......
}
instead of
double c[8];
if ( a == p ){
c[0]= .. ;
c[1]= .. ;
...
c[7] = ..;
} else if ( a == q) {
c[0]= .. ;
c[1]= .. ;
...
c[7] = ..;
} else if ( ... ) {
....
}
PS: There are 7 if conditions.
Assuming the values in each branch of the condition are not changing:
Have some value arrays values[NumConditions][8] and making c a pointer.
Then:
switch(a) {
case First: c = values[0]; break;
case ...
}
If values are defined on compile-time, you can use std::copy for example.
std::copy(std::begin(values), std::end(values), std::begin(c));
Prepare 7 arrays (or just a two-dimensional), which will be initialized at compile-time. Then, declare a pointer c. Afterwards, use a switch to select the desired array (i.e. c = valuesList[2]). If you need to write on that array, copy its contents outside of the switch.
If all initializers for a given condition are the same then you can use class std::array instead of the array. For example
std::array<double, 8> c;
if ( a == p ){
c.fill( 0 );
} else if ( a == q) {
c.fill( 1 ) ;
} else if (.. ){
......
}
IMHO create eight functions which you can give meaningful names that tell the next programmer (or yourself in one year) what the different eight configurations mean.
I admit it is a bit verbose but more importantly it makes the code clearer
if ( a == p )
{
setConfigValuesForProducingPannkakes(c);
}
else if ( a == q )
{
setConfigValuesForProducingWaffles(c);
}
...
Much cleaner approach .Use Switch case to avoid unnecessary comparisons
switch( a)
{
case p:
c[]={value1,valu2,...} ;
}
This is just an demo how to use:
int main()
{
int choice = 1;
switch( choice )
{
case 1: double c[8] = {0.123,32.33,33.02,66.44,0.11,45.08,44.9,0.0412};
break;
}
return 0;
}
std::array<double, 8> c;
if (a == p) {
c = {values};
} else if (a == q) {
c = {values};
} else if (...) {
...
}
Related
I'm solving a problem with a sorting non-redundant permutation of String Array.
For example, if input string is "8aC", then output should be order like {"Ca8","C8a", "aC8", "a8C", "8Ca", "9aC"}.I chose C++ data structure set because each time I insert the String into std:set, set is automatically sorted and eliminating redundancy. The output is fine.
But I WANT TO SORT SET IN DIFFERENT ALPHANUMERIC ORDER which is different from default alphanumeric sorting order. I want to customize the comparator of set the order priority like: upper case> lower case > digit.
I tried to customize comparator but it was quite frustrating. How can I customize the sorting order of the set? Here's my code.
set<string, StringCompare> setl;
for (i = 0; i < f; i++)
{
setl.insert(p[i]); //p is String Array. it has the information of permutation of String.
}
for (set<string>::iterator iter = setl.begin(); iter != setl.end(); ++iter)
cout << *iter << endl; //printing set items. it works fine.
struct StringCompare
{
bool operator () (const std::string s_left, const std::string s_right)
{
/*I want to use my character comparison function in here, but have no idea about that.
I'm not sure about that this is the right way to customize comparator either.*/
}
};
int compare_char(const char x, const char y)
{
if (char_type(x) == char_type(y))
{
return ( (int) x < (int) y) ? 1 : 0 ;
}
else return (char_type(x) > char_type(y)) ? 1 : 0;
}
int char_type(const char x)
{
int ascii = (int)x;
if (ascii >= 48 && ascii <= 57) // digit
{
return 1;
}
else if (ascii >= 97 && ascii <= 122) // lowercase
{
return 2;
}
else if (ascii >= 48 && ascii <= 57) // uppercase
{
return 3;
}
else
{
return 0;
}
}
You are almost there, but you should compare your string lexicographically.
I roughly added small changes to your code.
int char_type( const char x )
{
if ( isupper( x ) )
{
// upper case has the highest priority
return 0;
}
if ( islower( x ) )
{
return 1;
}
if ( isdigit( x ) )
{
// digit has the lowest priority
return 2;
}
// something else
return 3;
}
bool compare_char( const char x, const char y )
{
if ( char_type( x ) == char_type( y ) )
{
// same type so that we are going to compare characters
return ( x < y );
}
else
{
// different types
return char_type( x ) < char_type( y );
}
}
struct StringCompare
{
bool operator () ( const std::string& s_left, const std::string& s_right )
{
std::string::const_iterator iteLeft = s_left.begin();
std::string::const_iterator iteRight = s_right.begin();
// we are going to compare each character in strings
while ( iteLeft != s_left.end() && iteRight != s_right.end() )
{
if ( compare_char( *iteLeft, *iteRight ) )
{
return true;
}
if ( compare_char( *iteRight, *iteLeft ) )
{
return false;
}
++iteLeft;
++iteRight;
}
// either of strings reached the end.
if ( s_left.length() < s_right.length() )
{
return true;
}
// otherwise.
return false;
}
};
Your comparator is right. I would turn parameters to const ref like this
bool operator () (const std::string &s_left, const std::string &s_right)
and start by this simple implementation:
return s_left < s_right
This will give the default behaviour and give you confidence you are on the right track.
Then start comparing one char at the time with a for loop over the shorter between the length of the two strings. You can get chars out the string simply with the operator[] (e.g. s_left[i])
You're very nearly there with what you have.
In your comparison functor you are given two std::strings. What you need to do is to find the first position where the two strings differ. For that, you can use std::mismatch from the standard library. This returns a std::pair filled with iterators pointing to the first two elements that are different:
auto iterators = std::mismatch(std::begin(s_left), std::end(s_left),
std::begin(s_right), std::end(s_right));
Now, you can dereference the two iterators we've been given to get the characters:
char c_left = *iterators.first;
char c_right = *iterators.second;
You can pass those two characters to your compare_char function and it should all work :-)
Not absoloutely sure about this, but you may be able to use an enumerated class towards your advantage or an array and choose to read from certain indices in which ever order you like.
You can use one enumerated class to define the order you would like to output data in and another that contains the data to be outputed, then you can set a loop that keeps on looping to assign the value to the output in a permuted way!
namespace CustomeType
{
enum Outs { Ca8= 0,C8a, aC8, a8C, 8Ca, 9aC };
enum Order{1 = 0 , 2, 3 , 4 , 5};
void PlayCard(Outs input)
{
if (input == Ca8) // Enumerator is visible without qualification
{
string[] permuted;
permuted[0] = Outs[0];
permuted[1] = Outs[1];
permuted[2] = Outs[2];
permuted[3] = Outs[3];
permuted[4] = Outs[4];
}// else use a different order
else if (input == Ca8) // this might be much better
{
string[] permuted;
for(int i = 0; i<LessThanOutputLength; i++)
{
//use order 1 to assign values from Outs
}
}
}
}
This should work :
bool operator () (const std::string s_left, const std::string s_right)
{
for(int i = 0;i < s_left.size();i++){
if(isupper(s_left[i])){
if(isupper(s_right[i])) return s_left[i] < s_right[i];
else if(islower(s_right[i]) || isdigit(s_right[i]))return true;
}
else if(islower(s_left[i])){
if(islower(s_right[i])) return s_left[i] < s_right[i];
else if(isdigit(s_right[i])) return true;
else if(isupper(s_right[i])) return false;
}
else if(isdigit(s_left[i])){
if(isdigit(s_right[i])) return s_left[i] < s_right[i];
else if(islower(s_right[i]) || isupper(s_right[i])) return false;
}
}
}
I'm handling data in an if statement, and would like to keep that data as an not-locale variable, so I can call on it outside of the statement. Here's the actual code. Beware; it's pretty much just the outcast of an idea, but I'll welcome any and all ideas or better solutions (provided the suggestions aren't too advanced for my current level)...
The code creates and multidimensional char array (2 dimensions), and fills it. When trying to call on it afterwards, the programs crashes as a result of reaching a unassigned array value.
do
{
destRow = ( rand() % ROWS ) + 1; // assigning random placement for destroyer ship
destCol = ( rand() % COLLUMS ) + 1;
destDir = ( rand() % 2 ) + 1;
if ( destDir == 1 ) { //Destroyer: 1 = right
if ( destCol + 1 > COLLUMS ) {
continue;
} else {
char enemyDestroyer[DESTROYER_SIZE][2] = { { board[destCol][0] , board[0][destRow] }, { board[destCol + 1][0] , board[0][destRow] } };
}
} else if ( destDir == 2 ) { //Destroyer: 2 = down
if ( destRow + 1 > ROWS ) {
continue;
} else {
char enemyDestroyer[DESTROYER_SIZE][2] = { { board[destCol][0] , board[0][destRow] }, { board[destCol][0] , board[0][destRow + 1] } };
}
}
destSucces = true;
} while (!destSucces);
Here it checks the player input (gathered at some other point) with the data, set above, which hasn't actually been set to anything because the assignment happend in an if-statement
if ( ( input[0] == enemyDestroyer[0][0] && input[1] == enemyDestroyer[0][1] ) || (input[0] == enemyDestroyer[1][0] && input[1] == enemyDestroyer[1][1] ) ) {
cout << "Hit!" << endl;
board[posY][posX] = '!';
getchar();
//setting display damage
if ( input[1] == enemyDestroyer[0][1] ) {
enmDesDisp[0] = '!';
} else if ( input[1] == enemyDestroyer[1][1] ) {
enmDesDisp[1] = '!';
}
} else {
cout << endl << "Splash!" << endl;
}
It's not clear which array you are refering to. The only array you're interacting with in the code is enemyDestroyer, which is immediately released from memory after the assignment.
Perhaps you could expand you example so we can get a better understanding of what it is you're trying to do?
Update
To prevent enemyDestroyer from being instantly released youd have to move it to the appropriate scope. That would mean declaring it in the same scope it's going to be used.
I suggest reading up on scopes and perhaps switching to an object oriented design.
Suppose I have a while loop that depends on two separate inputs. In situation one, the while loop will take the value 1, and in situation two, it should take !cin.eof(). Is there a way I can do this efficiently? To be more concise:
string hello;
cin >> hello;
if(hello == "one")
{
//make the while loop depend on value 1
}
else if(hello == "two")
{
//make the while loop depend on value !cin.eof()
}
while(/*depends on above conditional*/)
{}
I don't want to do something like:
if(hello == "one)
{
while(1){}
}
else if(hello == "two")
{
while(!cin.eof){}
}
because the while loop essentially does the same thing in each situation.
For readability and in the interest of cohesion, I think you should move the contents of your loop into a separate function:
void DoSomething() { /* ... */ }
// ...
if(hello == "one)
{
while(1){ DoSomething(); }
}
else if(hello == "two")
{
while(!cin.eof){ DoSomething(); }
}
It's easier to see that the different while loops are doing the same thing but their conditions are different.
I believe you're looking for something like this:
while((hello == "one") || (hello == "two" && !cin.eof)) {
}
This code will do what you want, because it checks 'is the variable "one"? If so, keep executing. If it's not, it'll check: Is the variable "two"? If so, it'll check for cin.eof.
If it's neither, the loop won't execute. (the && 1 in the first condition was omitted, because it's always 'true', equalling and infinite loop)
Edit:
To simplify things, you may want to consider this code (as suggested in the comments):
bool HelloIsOne = (strcmp(hello, "one") == 0);
bool HelloIsTwo = (strcmp(hello, "two") == 0);
while(HelloIsOne || HelloIsTwo && !cin.eof) {
}
The brackets, which I placed in the previous example are actually unnecessary, because && binds stronger than ||, but they help the general clarity of the code.
Simply use or (||) as a condition in the while loop. Set the first condition if(hello == "one"). Now you have a while loop that will loop if one of the conditions is true.
bool value = hello == "one";
while (value || !cin.eof) {}
If you're using C++11:
#include <functional>
auto check = (hello == "one") ? []() bool -> { return 1; } :
[]() bool -> { return !cin.eof(); };
while(check) {
};
How about this:
switch(hello)
{
case 'one':
{
for(; 1; );
{
// your loop here
}
break;
}
case 'two':
{
for(;!cin.eof; )
{
// your other loop here
}
break;
}
default:
{
cout << " shouldnt get here unless bad user input" << endl;
break;
}
}
You can do something like this:
#include <iostream>
#include <string>
using namespace std;
int main()
{
string hello;
cin >> hello;
while(hello=="one"?1:(!cin.eof()))
{
//do stuff
}
return 0;
}
It checks if the string hello is "one" and if it's true, the condition of the while is 1, else it is !cin.eof() as you wanted.
Is there any way to return an array from a function? More specifically, I've created this function:
char bin[8];
for(int i = 7; i >= 0; i--)
{
int ascii='a';
if(2^i-ascii >= 0)
{
bin[i]='1';
ascii=2^i-ascii;
}
else
{
bin[i]='0';
}
}
and I need a way to return bin[].
You can't do that but you can:
return a dynamicaly allocated array - best owned by a smart pointer so that the caller does not have to care about deallocating memory for it - you could also return something like an std::vector this way.
populate an array/vector passed to you as an argument by pointer (suggested) or a non const reference.
Your array is a local variable allocated on the stack. You should use new [] to allocate it on the heap. Then you can just say: return bin;. Beware that you will have to explicitly free it with delete [] when you are done with it.
You are really asking the wrong question. If you want to do string processing in C++, use the std::string and/or std::vector classes, not arrays of char. Your code then becomes:
vector <char> func() {
vector <char> bin(8);
for( int i = 7; i >= 0; i-- ) {
int ascii='a';
if ( 2 ^ i - ascii >= 0 ) {
bin[i] = '1';
ascii = 2^i - ascii;
}
else {
bin[i] ='0';
}
}
return bin;
}
I think your best bet is to use a vector. It can function in many ways like an array and has several upsides (length stored with type, automatic memory management).
void Calculate( std::vector<char>& bin) {
for(int i = 7; i >= 0; i--)
{
int ascii='a';
if(2^i-ascii >= 0)
{
bin.push_back('1');
ascii=2^i-ascii;
}
else
{
bin.push_back('0');
}
}
}
If you want to return a copy of the array (might make sense for small arrays) and the array has fixed size, you can enclose it in a struct;
struct ArrayWrapper {
char _bin[8];
};
ArrayWrapper func()
{
ArrayWrapper x;
// Do your stuff here using x._bin instead of plain bin
return x;
}
Or just use a std::vector as has been already suggested.
Similar implemented to #ari's answer, i want to say there is already a boost solution, boost::array solving your problem:
boost::array<char, 8> f() {
boost::array<char, 8> bin;
for(int i = 7; i >= 0; i--) {
int ascii = 'a';
if(2 ^ i-ascii >= 0) {
bin[i] = '1';
ascii = 2 ^ i-ascii;
} else {
bin[i] = '0';
}
}
}
...
boost::array<char, 8> a(f());
[I'm not sure what you want to do with that algorithm though, but note that i think you want to do 1 << i (bit-wise shift) instead of 2 ^ i which is not exponentiation in C++.]
Boost array is a normal array, just wrapped in a struct, so you lose no performance what-so-ever. It will also be available in the next C++ version as std::array, and is very easy to do yourself if you don't need the begin()/size()/data()-sugar it adds (to be a container). Just go with the most basic one:
template<typename T, size_t S>
struct array {
T t[S];
T& operator[](ptrdiff_t i) { return t[i]; }
T const& operator[](ptrdiff_t i) const { return t[i]; }
};
But as usual, use the tools already written by other people, in this case boost::array. It's also got the advantage of being an aggregate (that's why it has no user declared constructor), so it allows initializing with a brace enclosed list:
boost::array<int, 4> a = {{ 1, 2, 3, 4 }};
you need to pass array bin as an argument in your function.
array always pass by address, therefore you dont need to return any value.
it will automatically show you all changes in your main program
void FunctionAbc(char bin[], int size);
void FuncationAbc(bin, size)
{
for(int i = 7; i >= 0; i--)
{
int ascii='a';
if(2^i-ascii >= 0)
{
bin[i]='1';
ascii=2^i-ascii;
}
else
{
bin[i]='0';
}
}
}
You'll want to pass by reference, as follows:
void modifyBin(char (&bin)[8])
{
/* your function goes here and modifies bin */
}
int main()
{
char bin[8];
modifyBin(bin);
/* bin has been updated */
return 0;
}
I think that everyone else answered this one... use a container instead of an array. Here's the std::string version:
std::string foo() {
int ascii = 'a';
std::string result("00000000");
for (int i=7; i>=0; --i) {
if (2^i-ascii >= 0) {
result[i] = '1';
ascii = 2^i-ascii;
}
}
return result;
}
I'm not really sure if 2^i-ascii is want you want or not. This will be parsed as (2 ^ (i - ascii)) which is a little strange.
I'm sorting strings that are comprised of text and numbers.
I want the sort to sort the number parts as numbers, not alphanumeric.
For example I want: abc1def, ..., abc9def, abc10def
instead of: abc10def, abc1def, ..., abc9def
Does anyone know an algorithm for this (in particular in c++)
Thanks
I asked this exact question (although in Java) and got pointed to http://www.davekoelle.com/alphanum.html which has an algorithm and implementations of it in many languages.
Update 14 years later: Dave Koelle’s blog has gone off line and I can’t find his actual algorithm, but here’s an implementation.
https://github.com/cblanc/koelle-sort
Several natural sort implementations for C++ are available. A brief review:
natural_sort<> - based on Boost.Regex.
In my tests, it's roughly 20 times slower than other options.
Dirk Jagdmann's alnum.hpp, based on Dave Koelle's alphanum algorithm
Potential integer overlow issues for values over MAXINT
Martin Pool's natsort - written in C, but trivially usable from C++.
The only C/C++ implementation I've seen to offer a case insensitive version, which would seem to be a high priority for a "natural" sort.
Like the other implementations, it doesn't actually parse decimal points, but it does special case leading zeroes (anything with a leading 0 is assumed to be a fraction), which is a little weird but potentially useful.
PHP uses this algorithm.
This is known as natural sorting. There's an algorithm here that looks promising.
Be careful of problems with non-ASCII characters (see Jeff's blog entry on the subject).
Partially reposting my another answer:
bool compareNat(const std::string& a, const std::string& b){
if (a.empty())
return true;
if (b.empty())
return false;
if (std::isdigit(a[0]) && !std::isdigit(b[0]))
return true;
if (!std::isdigit(a[0]) && std::isdigit(b[0]))
return false;
if (!std::isdigit(a[0]) && !std::isdigit(b[0]))
{
if (a[0] == b[0])
return compareNat(a.substr(1), b.substr(1));
return (toUpper(a) < toUpper(b));
//toUpper() is a function to convert a std::string to uppercase.
}
// Both strings begin with digit --> parse both numbers
std::istringstream issa(a);
std::istringstream issb(b);
int ia, ib;
issa >> ia;
issb >> ib;
if (ia != ib)
return ia < ib;
// Numbers are the same --> remove numbers and recurse
std::string anew, bnew;
std::getline(issa, anew);
std::getline(issb, bnew);
return (compareNat(anew, bnew));
}
toUpper() function:
std::string toUpper(std::string s){
for(int i=0;i<(int)s.length();i++){s[i]=toupper(s[i]);}
return s;
}
Usage:
std::vector<std::string> str;
str.push_back("abc1def");
str.push_back("abc10def");
...
std::sort(str.begin(), str.end(), compareNat);
To solve what is essentially a parsing problem a state machine (aka finite state automaton) is the way to go. Dissatisfied with the above solutions i wrote a simple one-pass early bail-out algorithm that beats C/C++ variants suggested above in terms of performance, does not suffer from numerical datatype overflow errors, and is easy to modify to add case insensitivity if required.
sources can be found here
For those that arrive here and are already using Qt in their project, you can use the QCollator class. See this question for details.
Avalanchesort is a recursive variation of naturall sort, whiche merge runs, while exploring the stack of sorting-datas. The algorithim will sort stable, even if you add datas to your sorting-heap, while the algorithm is running/sorting.
The search-principle is simple. Only merge runs with the same rank.
After finding the first two naturell runs (rank 0), avalanchesort merge them to a run with rank 1. Then it call avalanchesort, to generate a second run with rank 1 and merge the two runs to a run with rank 2. Then it call the avalancheSort to generate a run with rank 2 on the unsorted datas....
My Implementation porthd/avalanchesort divide the sorting from the handling of the data using interface injection. You can use the algorithmn for datastructures like array, associative arrays or lists.
/**
* #param DataListAvalancheSortInterface $dataList
* #param DataRangeInterface $beginRange
* #param int $avalancheIndex
* #return bool
*/
public function startAvalancheSort(DataListAvalancheSortInterface $dataList)
{
$avalancheIndex = 0;
$rangeResult = $this->avalancheSort($dataList, $dataList->getFirstIdent(), $avalancheIndex);
if (!$dataList->isLastIdent($rangeResult->getStop())) {
do {
$avalancheIndex++;
$lastIdent = $rangeResult->getStop();
if ($dataList->isLastIdent($lastIdent)) {
$rangeResult = new $this->rangeClass();
$rangeResult->setStart($dataList->getFirstIdent());
$rangeResult->setStop($dataList->getLastIdent());
break;
}
$nextIdent = $dataList->getNextIdent($lastIdent);
$rangeFollow = $this->avalancheSort($dataList, $nextIdent, $avalancheIndex);
$rangeResult = $this->mergeAvalanche($dataList, $rangeResult, $rangeFollow);
} while (true);
}
return $rangeResult;
}
/**
* #param DataListAvalancheSortInterface $dataList
* #param DataRangeInterface $range
* #return DataRangeInterface
*/
protected function findRun(DataListAvalancheSortInterface $dataList,
$startIdent)
{
$result = new $this->rangeClass();
$result->setStart($startIdent);
$result->setStop($startIdent);
do {
if ($dataList->isLastIdent($result->getStop())) {
break;
}
$nextIdent = $dataList->getNextIdent($result->getStop());
if ($dataList->oddLowerEqualThanEven(
$dataList->getDataItem($result->getStop()),
$dataList->getDataItem($nextIdent)
)) {
$result->setStop($nextIdent);
} else {
break;
}
} while (true);
return $result;
}
/**
* #param DataListAvalancheSortInterface $dataList
* #param $beginIdent
* #param int $avalancheIndex
* #return DataRangeInterface|mixed
*/
protected function avalancheSort(DataListAvalancheSortInterface $dataList,
$beginIdent,
int $avalancheIndex = 0)
{
if ($avalancheIndex === 0) {
$rangeFirst = $this->findRun($dataList, $beginIdent);
if ($dataList->isLastIdent($rangeFirst->getStop())) {
// it is the last run
$rangeResult = $rangeFirst;
} else {
$nextIdent = $dataList->getNextIdent($rangeFirst->getStop());
$rangeSecond = $this->findRun($dataList, $nextIdent);
$rangeResult = $this->mergeAvalanche($dataList, $rangeFirst, $rangeSecond);
}
} else {
$rangeFirst = $this->avalancheSort($dataList,
$beginIdent,
($avalancheIndex - 1)
);
if ($dataList->isLastIdent($rangeFirst->getStop())) {
$rangeResult = $rangeFirst;
} else {
$nextIdent = $dataList->getNextIdent($rangeFirst->getStop());
$rangeSecond = $this->avalancheSort($dataList,
$nextIdent,
($avalancheIndex - 1)
);
$rangeResult = $this->mergeAvalanche($dataList, $rangeFirst, $rangeSecond);
}
}
return $rangeResult;
}
protected function mergeAvalanche(DataListAvalancheSortInterface $dataList, $oddListRange, $evenListRange)
{
$resultRange = new $this->rangeClass();
$oddNextIdent = $oddListRange->getStart();
$oddStopIdent = $oddListRange->getStop();
$evenNextIdent = $evenListRange->getStart();
$evenStopIdent = $evenListRange->getStop();
$dataList->initNewListPart($oddListRange, $evenListRange);
do {
if ($dataList->oddLowerEqualThanEven(
$dataList->getDataItem($oddNextIdent),
$dataList->getDataItem($evenNextIdent)
)) {
$dataList->addListPart($oddNextIdent);
if ($oddNextIdent === $oddStopIdent) {
$restTail = $evenNextIdent;
$stopTail = $evenStopIdent;
break;
}
$oddNextIdent = $dataList->getNextIdent($oddNextIdent);
} else {
$dataList->addListPart($evenNextIdent);
if ($evenNextIdent === $evenStopIdent) {
$restTail = $oddNextIdent;
$stopTail = $oddStopIdent;
break;
}
$evenNextIdent = $dataList->getNextIdent($evenNextIdent);
}
} while (true);
while ($stopTail !== $restTail) {
$dataList->addListPart($restTail);
$restTail = $dataList->getNextIdent($restTail);
}
$dataList->addListPart($restTail);
$dataList->cascadeDataListChange($resultRange);
return $resultRange;
}
}
My algorithm with test code of java version. If you want to use it in your project you can define a comparator yourself.
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import java.util.function.Consumer;
public class FileNameSortTest {
private static List<String> names = Arrays.asList(
"A__01__02",
"A__2__02",
"A__1__23",
"A__11__23",
"A__3++++",
"B__1__02",
"B__22_13",
"1_22_2222",
"12_222_222",
"2222222222",
"1.sadasdsadsa",
"11.asdasdasdasdasd",
"2.sadsadasdsad",
"22.sadasdasdsadsa",
"3.asdasdsadsadsa",
"adsadsadsasd1",
"adsadsadsasd10",
"adsadsadsasd3",
"adsadsadsasd02"
);
public static void main(String...args) {
List<File> files = new ArrayList<>();
names.forEach(s -> {
File f = new File(s);
try {
if (!f.exists()) {
f.createNewFile();
}
files.add(f);
} catch (IOException e) {
e.printStackTrace();
}
});
files.sort(Comparator.comparing(File::getName));
files.forEach(f -> System.out.print(f.getName() + " "));
System.out.println();
files.sort(new Comparator<File>() {
boolean caseSensitive = false;
int SPAN_OF_CASES = 'a' - 'A';
#Override
public int compare(File left, File right) {
char[] csLeft = left.getName().toCharArray(), csRight = right.getName().toCharArray();
boolean isNumberRegion = false;
int diff=0, i=0, j=0, lenLeft=csLeft.length, lenRight=csRight.length;
char cLeft = 0, cRight = 0;
for (; i<lenLeft && j<lenRight; i++, j++) {
cLeft = getCharByCaseSensitive(csLeft[i]);
cRight = getCharByCaseSensitive(csRight[j]);
boolean isNumericLeft = isNumeric(cLeft), isNumericRight = isNumeric(cRight);
if (isNumericLeft && isNumericRight) {
// Number start!
if (!isNumberRegion) {
isNumberRegion = true;
// Remove prefix '0'
while (i < lenLeft && cLeft == '0') i++;
while (j < lenRight && cRight == '0') j++;
if (i == lenLeft || j == lenRight) break;
}
// Diff start: calculate the diff value.
if (cLeft != cRight && diff == 0)
diff = cLeft - cRight;
} else {
if (isNumericLeft != isNumericRight) {
// One numeric and one char.
if (isNumberRegion)
return isNumericLeft ? 1 : -1;
return cLeft - cRight;
} else {
// Two chars: if (number) diff don't equal 0 return it.
if (diff != 0)
return diff;
// Calculate chars diff.
diff = cLeft - cRight;
if (diff != 0)
return diff;
// Reset!
isNumberRegion = false;
diff = 0;
}
}
}
// The longer one will be put backwards.
return (i == lenLeft && j == lenRight) ? cLeft - cRight : (i == lenLeft ? -1 : 1) ;
}
private boolean isNumeric(char c) {
return c >= '0' && c <= '9';
}
private char getCharByCaseSensitive(char c) {
return caseSensitive ? c : (c >= 'A' && c <= 'Z' ? (char) (c + SPAN_OF_CASES) : c);
}
});
files.forEach(f -> System.out.print(f.getName() + " "));
}
}
The output is,
1.sadasdsadsa 11.asdasdasdasdasd 12_222_222 1_22_2222 2.sadsadasdsad 22.sadasdasdsadsa 2222222222 3.asdasdsadsadsa A__01__02 A__11__23 A__1__23 A__2__02 A__3++++ B__1__02 B__22_13 adsadsadsasd02 adsadsadsasd1 adsadsadsasd10 adsadsadsasd3
1.sadasdsadsa 1_22_2222 2.sadsadasdsad 3.asdasdsadsadsa 11.asdasdasdasdasd 12_222_222 22.sadasdasdsadsa 2222222222 A__01__02 A__1__23 A__2__02 A__3++++ A__11__23 adsadsadsasd02 adsadsadsasd1 adsadsadsasd3 adsadsadsasd10 B__1__02 B__22_13
Process finished with exit code 0
// -1: s0 < s1; 0: s0 == s1; 1: s0 > s1
static int numericCompare(const string &s0, const string &s1) {
size_t i = 0, j = 0;
for (; i < s0.size() && j < s1.size();) {
string t0(1, s0[i++]);
while (i < s0.size() && !(isdigit(t0[0]) ^ isdigit(s0[i]))) {
t0.push_back(s0[i++]);
}
string t1(1, s1[j++]);
while (j < s1.size() && !(isdigit(t1[0]) ^ isdigit(s1[j]))) {
t1.push_back(s1[j++]);
}
if (isdigit(t0[0]) && isdigit(t1[0])) {
size_t p0 = t0.find_first_not_of('0');
size_t p1 = t1.find_first_not_of('0');
t0 = p0 == string::npos ? "" : t0.substr(p0);
t1 = p1 == string::npos ? "" : t1.substr(p1);
if (t0.size() != t1.size()) {
return t0.size() < t1.size() ? -1 : 1;
}
}
if (t0 != t1) {
return t0 < t1 ? -1 : 1;
}
}
return i == s0.size() && j == s1.size() ? 0 : i != s0.size() ? 1 : -1;
}
I am not very sure if it is you want, anyway, you can have a try:-)