Thread: Remove comma from a string

You have a string which stores a number with commas. For example, a string that has the number 345,000,000. How will you manipulate this string in-place [without using any extra memory] so that the output is the original string without any commas in O(n) ?

Code:

int nLen = strlen(str);
char* pWriteTo = str;
char* pReadFrom = str;
for (int i = 0; i < nLen; i++)
{
  if (*pReadFrom != ',')
  {
    *pWriteTo = *pReadFrom;
    pWriteTo++;
  }
  pReadFrom++;
}