Adding Space to String at certain places in C++ - c++

Question

I am having trouble figuring out the process to add a space in a string at capital letters in C++. If I have a string "HelloWorld", how do I convert that to "Hello World"?
I've tried using substrings and the isupper function but I can't get anything to work.
Edit: this is the code I have. I don't understand why in = newname is not valid code.
string breakStringAtCaps(string in) {
string newname[10];
int j = 0;
for (int i = 0; i < in.size(); i++) {
if (isupper(in[i]) && i != 0) {
newname[j] = " ";
j++;
}
newname[j] = in[i];
j++;
}
in = newname;
return in;
}

Answer 1

You can do it like this:
string breakStringAtCaps(const string& in)
{
string newname;
for(int i = 0; i < in.size(); i++)
{
if(isupper(in[i]) && i != 0)
newname += " ";
newname += in[i];
}
return newname;
}

Answer 2

You are thinking right in thinking substr, but you implementation is a bit off. If creating an new string containing the contents of the original and inserting a ' ' (space) before each upper-case letter (not including the first), you can seed the new string with the first character of the original using substr(0,1) and then use an auto ranged for loop and substr(1) to evaluate each character after the first.
The loop along with a check of isupper() is basically all you need, e.g.
#include <iostream>
#include <string>
#include <cctype>
int main (int argc, char **argv) {
std::string s = argc > 1 ? argv[1] : "HelloWorld",
snew = s.substr (0,1);
if (s.size() > 0)
for (auto& c : s.substr(1)) {
if (std::isupper (c))
snew += " ";
snew += c;
}
std::cout << snew << '\n';
}
(the program will use "HelloWorld" by default if no string is given as an argument on the command line, otherwise the string given on the command line is used)
Example Use/Output
$ ./bin/spacebeforeupper
Hello World
Or with a string given as an argument:
$ ./bin/spacebeforeupper MyDogHasFleas
My Dog Has Fleas

Answer 3

You can iterate through the strin characters, check if it is a cap and insert a ' ' before if it is one:
It should look like:
for(int i=0; i < str.length(); i++)
{
if (str[i]>='A' && str[i]<='Z')
{
if (i != 0)
cout << " ";
cout << str[i];
}
else
{
cout << str[i];
}
}

Answer 4

I just give a implementation, maybe not the best solution:
#include <string>
#include <ctype.h>
void breakStringAtCaps(std::string& in) {
std::string::const_iterator it = in.begin();
while(it != in.end()) {
if(it != in.begin() && isupper(*it)) {
in.insert(it, ' ');
it += 2;
}
else
++it;
}
}
//
#include <iostream>
int main(int argc, char** argv) {
std::string str("HelloWorld;");
breakStringAtCaps(str);
std::cout << str.c_str() << std::endl;
return 0;
}
and in your code,
string newname[10];
here 'newname' is a string array's name. you should not assign the name of array to a string instance.
and newname[i] means the i-th string of the array, not the i-th char of a string named 'newname' as you desired.