#include <iostream>
#include <fstream>
#include <cmath>
using namespace std;
char* typein(char* text)
{
int count=0;
ifstream srcFile("in.txt", ios::in);
if (!srcFile)
{
cout << "error opening source file." << endl;
return 0;
}
char x;
while (srcFile >> x)
{
if (x >= 'a' && x <= 'z')
text[count] = x;
else if (x >= 'A' && x <= 'Z')
text[count] = x + 32;
else
text[count] = ' ';
count++;
}
srcFile.close();
return text;
}
double cal1(double* all1,char* text)
{
int t,count=0;
while(all1[count])
{
t = all1[count] - 'a' ;
count++;
if (t >= 0 && t <= 25)
all1[t]++;
else
all1[26]++;
}
all1[27] =count ;
double p, cal1 = 0;
for (t = 0; t <= 26; t++)
{
p = (all1[t] / all1[27]);
all1[t] = p * log(p);
}
for (t = 0; t <= 26; t++)
{
cal1 -= all1[t];
}
return cal1;
}
int main()
{
char *text = new char[30000]();
double *all = new double[28]();
double t2,result1=0,result2=0;
text = typein(text);
result1 = cal1(all,text);
cout <<result1 << endl;
delete[] all;
delete[] text;
return 0;
}
from a period of code that calculate a double number ,instead of receiving a number from the result, I still got a “-nan.(ind)” which is not a number. Besides, I have used the function of double *all = new double28,but there is still no error or bugs showing up.
Loop while(all1[count]) never would be executed because all elements of array are zero.
Therefore count is zero, all1[27] is zero.
Therefore p = all1[t] / all1[27] is 0.0/0.0, which is NaN, so only value you able to write into array is NaN.
Related
I built a program in C++ that takes words from txt file and inputs into program. Program then stores these words into array. Now, I want to search a specific word among the array using binary search.
My txt file has the following words:
hello
world
hi
how
are
you
i
am
fine
thank
welcome
#include <iostream>
#include <fstream>
#include <string>
#include <cstring>
using namespace std;
int binarySearch(string words[], const string& x,int n)
{
int l = 0 ;
int r = n - 1;
while (l <= r)
{
int m = l + (r - l) / 2;
int res;
if (x == (words[m]))
res = 0;
// Check if x is present at mid
if (res == 0)
return m;
// If x greater, ignore left half
if (x > (words[m]))
l = m + 1;
// If x is smaller, ignore right half
else
r = m - 1;
}
return -1;
}
int main () {
ifstream inFile;
inFile.open("test.txt");
if(inFile.fail()){
cerr << "Error opening file"<< endl ;
exit(1);
}
string x1;
string words[100];
int count=0,i=0;
string str;
while( !inFile.eof()) {
inFile >> x1;
words[i]=x1;
count++;
i++;
}
for (i=0;i<100;i++){
cout<< words[i]<<endl;
}
string x;
x = "how";
int n = 14;
int result = binarySearch(words , x,n);
if (result == -1)
cout << ("\nElement not present");
else
cout << ("Element found at index ") << result;
return 0;
}
I can't find the words except Hello which is the first word. So please help me.
hopefully this work
#include <iostream>
#include <fstream>
#include <string>
#include <cstring>
using namespace std;
int binarySearch(string words[], const string& x, int n)
{
int l = 0;
int r = n - 1;
while (l <= r)
{
int m = l + (r - l) / 2;
int res = 0;
if (x == (words[m]))
res = 0;
// Check if x is present at mid
if (res == 0)
return m;
// If x greater, ignore left half
if (x > (words[m]))
l = m + 1;
// If x is smaller, ignore right half
else
r = m - 1;
}
return -1;
}
int main() {
ifstream inFile;
inFile.open("test.txt");
if (inFile.fail()) {
cerr << "Error opening file" << endl;
exit(1);
}
string x1;
string words[100];
int count = 0, i = 0;
string str;
while (!inFile.eof()) {
inFile >> x1;
words[i] = x1;
count++;
i++;
}
for (i = 0; i < 100; i++) {
cout << words[i] << endl;
}
string x;
x = "fine";
int n = 11;
int result = binarySearch(words, x, n);
if (result == -1)
cout << ("\nElement not present");
else
cout << ("Element found at index ") << result;
return 0;
}
I am trying to write a code that takes a binary number input as a string and will only accept 1's or 0's if not there should be an error message displayed. Then it should go through a loop digit by digit to convert the binary number as a string to decimal. I cant seem to get it right I have the fact that it will only accept 1's or 0's correct. But then when it gets into the calculations something messes up and I cant seem to get it correct. Currently this is the closest I believe I have to getting it working. could anyone give me a hint or help me with what i am doing wrong?
#include <iostream>
#include <string>
using namespace std;
string a;
int input();
int main()
{
input();
int decimal, x= 0, length, total = 0;
length = a.length();
// atempting to make it put the digits through a formula backwords.
for (int i = length; i >= 0; i--)
{
// Trying to make it only add the 2^x if the number is 1
if (a[i] = '1')
{
//should make total equal to the old total plus 2^x if a[i] = 1
total = total + pow(x,2);
}
//trying to let the power start at 0 and go up each run of the loop
x++;
}
cout << endl << total;
int stop;
cin >> stop;
return 0;
}
int input()
{
int x, x2, count, repeat = 0;
while (repeat == 0)
{
cout << "Enter a string representing a binary number => ";
cin >> a;
count = a.length();
for (x = 0; x < count; x++)
{
if (a[x] != '0' && a[x] != '1')
{
cout << a << " is not a string representing a binary number>" << endl;
repeat = 0;
break;
}
else
repeat = 1;
}
}
return 0;
}
I don't think that pow suits for integer calculation. In this case, you can use shift operator.
a[i] = '1' sets the value of a[i] to '1' and return '1', which is always true.
You shouldn't access a[length], which should be meaningless.
fixed code:
int main()
{
input();
int decimal, x= 0, length, total = 0;
length = a.length();
// atempting to make it put the digits through a formula backwords.
for (int i = length - 1; i >= 0; i--)
{
// Trying to make it only add the 2^x if the number is 1
if (a[i] == '1')
{
//should make total equal to the old total plus 2^x if a[i] = 1
total = total + (1 << x);
}
//trying to let the power start at 0 and go up each run of the loop
x++;
}
cout << endl << total;
int stop;
cin >> stop;
return 0;
}
I would use this approach...
#include <iostream>
using namespace std;
int main()
{
string str{ "10110011" }; // max length can be sizeof(int) X 8
int dec = 0, mask = 1;
for (int i = str.length() - 1; i >= 0; i--) {
if (str[i] == '1') {
dec |= mask;
}
mask <<= 1;
}
cout << "Decimal number is: " << dec;
// system("pause");
return 0;
}
Works for binary strings up to 32 bits. Swap out integer for long to get 64 bits.
#include <iostream>
#include <stdio.h>
#include <string>
using namespace std;
string getBinaryString(int value, unsigned int length, bool reverse) {
string output = string(length, '0');
if (!reverse) {
for (unsigned int i = 0; i < length; i++) {
if ((value & (1 << i)) != 0) {
output[i] = '1';
}
}
}
else {
for (unsigned int i = 0; i < length; i++) {
if ((value & (1 << (length - i - 1))) != 0) {
output[i] = '1';
}
}
}
return output;
}
unsigned long getInteger(const string& input, size_t lsbindex, size_t msbindex) {
unsigned long val = 0;
unsigned int offset = 0;
if (lsbindex > msbindex) {
size_t length = lsbindex - msbindex;
for (size_t i = msbindex; i <= lsbindex; i++, offset++) {
if (input[i] == '1') {
val |= (1 << (length - offset));
}
}
}
else { //lsbindex < msbindex
for (size_t i = lsbindex; i <= msbindex; i++, offset++) {
if (input[i] == '1') {
val |= (1 << offset);
}
}
}
return val;
}
int main() {
int value = 23;
cout << value << ": " << getBinaryString(value, 5, false) << endl;
string str = "01011";
cout << str << ": " << getInteger(str, 1, 3) << endl;
}
I see multiple misstages in your code.
Your for-loop should start at i = length - 1 instead of i = length.
a[i] = '1' sets a[i] to '1' and does not compare it.
pow(x,2) means and not . pow is also not designed for integer operations. Use 2*2*... or 1<<e instead.
Also there are shorter ways to achieve it. Here is a example how I would do it:
std::size_t fromBinaryString(const std::string &str)
{
std::size_t result = 0;
for (std::size_t i = 0; i < str.size(); ++i)
{
// '0' - '0' == 0 and '1' - '0' == 1.
// If you don't want to assume that, you can use if or switch
result = (result << 1) + str[i] - '0';
}
return result;
}
#include <cstdlib>
#include <iostream>
#include <Math.h>
#include <algorithm>
#include <string>
#include <iterator>
#include <iostream>
#include <vector> // std::vector
using namespace std;
int stepCount, i, x, y, z, j, k, array1Size, array2Size, tester, checker;
int numstring[10] = { 0,1,2,3,4,5,6,7,8,9 };
int numstringTest[10] = { 0,1,2,3,4,5,6,7,7,9 };
int* numbers;
int* differentNumbers;
int* p;
int* otherNumbers;
void stepCounter(int a) {
// determines the step number of the number
if (a / 10 == 0)
stepCount = 1;
else if (a / 100 == 0)
stepCount = 2;
else if (a / 1000 == 0)
stepCount = 3;
else if (a / 10000 == 0)
stepCount = 4;
else if (a / 100000 == 0)
stepCount = 5;
else if (a / 1000000 == 0)
stepCount = 6;
else if (a / 10000000 == 0)
stepCount = 7;
else if (a / 100000000 == 0)
stepCount = 8;
else if (a / 1000000000 == 0)
stepCount = 9;
}
void stepIndicator(int b) {
// indicates each step of the number and pass them into array 'number'
stepCounter(b);
numbers = new int[stepCount];
for (i = stepCount; i>0; i--) {
//
/*
x = (round(pow(10,stepCount+1-i)));
y = (round(pow(10,stepCount-i)));
z = (round(pow(10,stepCount-i)));
*/
x = (int)(pow(10, stepCount + 1 - i) + 0.5);
y = (int)(pow(10, stepCount - i) + 0.5);
numbers[i - 1] = (b%x - b%y) / y;
}
}
int sameNumberCheck(int *array, int arraySize) {
//checks if the array has two or more of same integer inside return 1 if same numbers exist, 0 if not
for (i = 0; i<arraySize - 1; i++) {
//
for (j = i + 1; j<arraySize; j++) {
//
if (array[i] == array[j]) {
//
return 1;
}
}
}
return 0;
}
void getDifferentNumbers(int* array, int arraySize) {
//
k = 0;
j = 0;
checker = 0;
otherNumbers = new int[10 - arraySize]; //exact number of other numbers is 10 - numbers we have
for (i = 0; i<10; i++) {
if ((i>0)&(checker = 0)) {
k++;
otherNumbers[k - 1] = i - 1;
}
//
checker = 0;
for (j = 0; j<arraySize; j++) {
//
p = array + j;
cout << *p << endl; //ilkinde doğru sonra yanlış yapıyor?!
if (*p = i) {
checker++;
}
}
}
}
int main(int argc, char *argv[])
{
stepCounter(999999);
cout << stepCount << endl;
stepIndicator(826424563);
for (j = 0; j<9; j++) {
//
cout << numbers[j] << endl;
}
cout << sameNumberCheck(numstringTest, 10) << " must be 1" << endl;
cout << sameNumberCheck(numstring, 10) << " must be 0" << endl;
cout << endl;
getDifferentNumbers(numstringTest, 10);
cout << endl;
cout << endl << otherNumbers[0] << " is the diff number" << endl;
system("PAUSE");
return EXIT_SUCCESS;
}
Hi, my problem is with pointers actually. You will see above, function getDifferentNumbers. It simply does a comparement if in any given array there are repeated numbers(0-9). To do that, I passed a pointer to the function. I simply do the comparement via pointer. However, there is a strange thing here. When I execute, first time it does correct, but secon time it goes completely mad! This is the function:
void getDifferentNumbers(int* array, int arraySize) {
//
k = 0;
j = 0;
checker = 0;
otherNumbers = new int[10 - arraySize]; //exact number of other numbers is 10 - numbers we have
for (i = 0; i<10; i++) {
if ((i>0)&(checker = 0)) {
k++;
otherNumbers[k - 1] = i - 1;
}
//
checker = 0;
for (j = 0; j<arraySize; j++) {
//
p = array + j;
cout << *p << endl; //ilkinde doğru sonra yanlış yapıyor?!
if (*p = i) {
checker++;
}
}
}
}
and this is the array I passed into the function:
int numstringTest[10] = {0,1,2,3,4,5,6,7,7,9};
it should give the number 7 in otherNumbers[0], however it does not. And I do not know why. I really can not see any wrong statement or operation here. When I execute, it first outputs the correct values of
numstringTest: 1,2,3,4,5,6,7,7,9
but on next 9 iteration of for loop it outputs:
000000000011111111112222222222333333333344444444445555555555666666666677777777778888888888
You have some basic problems in your code.
There are multiple comparisons that are not really comparisons, they're assignments. See the following:
if((i>0) & (checker=0)){
and
if(*p = i){
In both cases you're assigning values to the variables, not comparing them. An equality comparison should use ==, not a single =. Example:
if (checker == 0) {
Besides that, you're using & (bitwise AND) instead of && (logical AND), which are completely different things. You most likely want && in your if statement.
I've just noticed this:
getDifferentNumbers(numstringTest, 10);
and in that function:
otherNumbers = new int[10 - arraySize];
which doesn't seem right.
I have this program that graphs simple parametric equations on a board of a defined length and width by me. It compiles fine but prints multiple instances of the function in different positions of the graph. If someone could please help me figure out why I am getting this output, I would greatly appreciate it. I included comments throughout the code to help understand what is going on.
I do not have enough reputation to post a picture of the output but if you compile and execute it you will see what I am talking about.
#include <iostream>
#include <cstdlib>
#include <unistd.h>
#include <time.h>
#include <cmath>
using namespace std;
#define N 25
#define M 60
/*
This function prints the board each time it is called and places an *
in the place corresponding to the value of the function.
*/
void print_board(char p[M][N]) {
int i, j;
for (i=0; i<=N; i++) {
for (j=0; j<=M; j++)
if (i==0) cout << '=';
else if (j==0) cout << '|';
else if (i==N) cout << '=';
else if (j==M) cout << '|';
else if (p[i][j]== '*') cout << '*';
else cout << ' ';
cout << endl;
}
}
/*
These functions accepts an integer for time and computes a value for x and y
for the parametirc equations given and returns each.
*/
int fx(int t) {
int x = t;
return x;
}
int fy(int t) {
//int y = 5 * sin(0.2 * t) + 15;
int y = (pow(t,2)/60) - t + 25;
return y;
}
/*
This function copies the old board and comoputes what the new board is.
*/
void next_board(char p[M][N], int t) {
int i, j;
//copies the old board
int q[M][N];
for (i=0; i<=N; i++) {
for (j=0; j<=M; j++) {
q[i][j] = p[i][j];
}
}
//creates the new board
int x, y;
for (i=0; i<=N; i++) {
for (j=0; j<=M; j++) {
x = fx(t);
y = fy(t);
if (i == y && j == x) {
p[i][j] = '*'; //stores an * for the values of x and y
}
}
}
}
int main() {
char p[M][N];
print_board(p);
int t = 0;
while(t <= M) {
cout << string(80, '\n');
next_board(p , t);
print_board(p);
usleep(20000);
t++;
}
return 0;
}
Please help and thank you for all who try!
everywhere in your program where you have
char p[M][N]
change them to
char p[N][M]
and you should get the results that youd expect, your mixing axes in your program
heres the whole working code if youd like
#include <iostream>
#include <cstdlib>
#include <unistd.h>
#include <time.h>
#include <cmath>
#include <string>
using namespace std;
#define N 25
#define M 60
/*
This function prints the board each time it is called and places an *
in the place corresponding to the value of the function.
*/
void print_board(char p[N][M]) {
int i, j;
for (i = 0; i <= N; i++) {
for (j = 0; j <= M; j++)
if (i == 0) cout << '=';
else if (j == 0) cout << '|';
else if (i == N) cout << '=';
else if (j == M) cout << '|';
else if (p[i][j] == '*') cout << '*';
else cout << ' ';
cout << endl;
}
}
/*
These functions accepts an integer for time and computes a value for x and y
for the parametirc equations given and returns each.
*/
int fx(int t) {
int x = t;
return x;
}
int fy(int t) {
//int y = 5 * sin(0.2 * t) + 15;
int y = (pow(t, 2) / 60) - t + 25;
return y;
}
/*
This function copies the old board and comoputes what the new board is.
*/
void next_board(char p[N][M], int t) {
int i, j;
//copies the old board
int q[M][N];
for (i = 0; i <= N; i++) {
for (j = 0; j <= M; j++) {
q[i][j] = p[i][j];
}
}
//creates the new board
int x, y;
for (i = 0; i <= N; i++) {
for (j = 0; j <= M; j++) {
x = fx(t);
y = fy(t);
if (i == y && j == x) {
p[i][j] = '*'; //stores an * for the values of x and y
}
}
}
}
int main() {
char p[N][M];
print_board(p);
int t = 0;
while (t <= M) {
cout << string(80, '\n');
next_board(p, t);
print_board(p);
usleep(20000);
t++;
}
return 0;
}
I need to create a generic function that changes from any starting base, to any final base. I have everything down, except my original function took (and takes) an int value for the number that it converts to another base. I decided to just overload the function. I am Ok with changing between every base, but am slightly off when using my new function to take in a string hex value.
The code below should output 1235 for both functions. It does for the first one, but for the second, I am currently getting 1347. Decimal to Hex works fine - It's just the overloaded function (Hex to anything else) that is slightly off.
Thanks.
#include <iostream>
#include <stack>
#include <string>
#include <cmath>
using namespace std;
void switchBasesFunction(stack<int> & myStack, int startBase, int finalBase, int num);
void switchBasesFunction(stack<int> & myStack, int startBase, int finalBase, string s);
int main()
{
stack<int> myStack;
string hexNum = "4D3";
switchBasesFunction(myStack, 8, 10, 2323);
cout << endl << endl;
switchBasesFunction(myStack, 16, 10, hexNum);
return 0;
}
void switchBasesFunction(stack<int> & myStack, int startBase, int finalBase, int num)
{
int totalVal = 0;
string s = to_string(num);
for (int i = 0; i < s.length(); i++)
{
myStack.push(s.at(i) - '0');
}
int k = 0;
while (myStack.size() > 0)
{
totalVal += (myStack.top() * pow(startBase, k++));
myStack.pop();
}
string s1;
while (totalVal > 0)
{
int temp = totalVal % finalBase;
totalVal = totalVal / finalBase;
char c;
if (temp < 10)
{
c = temp + '0';
s1 += c;
}
else
{
c = temp - 10 + 'A';
s1 += c;
}
}
for (int i = s1.length() - 1; i >= 0; i--)
{
cout << s1[i];
}
cout << endl << endl;
}
void switchBasesFunction(stack<int> & myStack, int startBase, int finalBase, string s)
{
int totalVal = 0;
for (int i = 0; i < s.length(); i++)
{
myStack.push(s.at(i) - '0');
}
int k = 0;
while (myStack.size() > 0)
{
totalVal += (myStack.top() * pow(startBase, k++));
myStack.pop();
}
string s1;
while (totalVal > 0)
{
int temp = totalVal % finalBase;
totalVal = totalVal / finalBase;
char c;
if (temp < 10)
{
c = temp + '0';
s1 += c;
}
else
{
c = temp - 10 + 'A';
s1 += c;
}
}
for (int i = s1.length() - 1; i >= 0; i--)
{
cout << s1[i];
}
cout << endl << endl;
}
Sorry, but I'm having issues understanding your code, so I thought I'd simplify it.
Here's the algorithm / code (untested):
void convert_to_base(const std::string& original_value,
unsigned int original_base,
std::string& final_value_str,
unsigned int final_base)
{
static const std::string digit_str =
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if ((original_base > digit_str.length()) || (final_base > digit_str.length())
{
std::cerr << "Base value exceeds limit of " << digit_str.length() << ".\n";
return;
}
// Parse string from right to left, smallest value to largest.
// Convert to decimal.
unsigned int original_number = 0;
unsigned int digit_value = 0;
int index = 0;
for (index = original_value.length(); index > 0; --index)
{
std::string::size_type posn = digit_str.find(original_value[index];
if (posn == std::string::npos)
{
cerr << "unsupported digit encountered: " << original_value[index] << ".\n";
return;
}
digit_value = posn;
original_number = original_number * original_base + digit_value;
}
// Convert to a string of digits in the final base.
while (original_number != 0)
{
digit_value = original_number % final_base;
final_value_str.insert(0, 1, digit_str[digit_value]);
original_number = original_number / final_base;
}
}
*Warning: code not tested via compiler.**