Character missing from output c++

Question

I was trying to solve a problem from codewars and it seems like I have a problem with my output.

This is the problem I am trying to solve

This is my output and my code

The code works when I run it on codeblocks. There is a missing " in the output and I think that is due to the NULL character that I am adding at the end of the string. My code is not meant to output any quotation marks, and I think that the NULL character interferes with the website's code, erasing their last quotation mark. Can anybody help me? Thank you! This is the code:

#include <string.h>

std::string to_camel_case(std::string a)
{
    int q = a.size();
    for (int i = 0; i < q; i++)
        if (a[i] == '-' || a[i] == '_') {
            if (a[0] > 96 && a[0] < 123)
                a[i + 1] = a[i + 1] - 32;
            for (int j = i; j < q - 1; j++) {
                a[j] = a[j + 1];
            }
            a[q - 1] = 0;
        }
    return a;
}

Answer 1

Have you tried resizing the string before returning it?

std::string to_camel_case(std::string a)
{
  int q = a.size();
  int count = 0;
  for (int i = 0; i < q; i++)
  {
    if (a[i] == '-' || a[i] == '_')
    {
      if (a[0] > 96 && a[0] < 123)
        a[i + 1] = a[i + 1] - 32;

      for (int j = i; j < q - 1; j++)
        a[j] = a[j + 1];

      // Keep track of the amount to remove
      count++;
    }
  }

  if (count)
    a.resize(q - count);

  return a;
}

Answer 2

It seems like you're making it way more complicated than it needs to be which is causing simple mistakes to be overlooked. Modern C++ practices tries to alleviate these concerns by doing the work for you, such as iterating over a container and erasing a specified element from that container.

#include <algorithm>
#include <string>
#include <iostream>
#include <cctype>

std::string ToCamelCase(std::string str) noexcept {
    if(str.empty()) return {};
    for(auto iter = std::begin(str); iter != std::end(str) - 1; /* DO NOTHING */ ) {
        if(*iter == '-' || *iter == '_') {
            iter = str.erase(iter);
            *iter = static_cast<char>(std::toupper(*iter));
            continue;
        }
        ++iter;
    }
    return str;
}

I only wish I knew of an STL algorithm that had look-ahead capabilities. That way this could be a simple call to a std::transform-like function.