DSXchange

Code: Select all

#include "stdio.h"
#include "string.h"
#include "stdlib.h"

char* pxEreplace(char *str, char *subStr, char *rep, int num, int beg)
{
  char *result = (char *)malloc (sizeof(char *));
  int newlen = strlen(rep);
  int oldlen = strlen(subStr);
  int i, x, count = 0;
 
  //If begining is less than or equal to 1 then default it to 1
  if (beg <= 1)
  {beg = 1;}

  //replace all instances if value of num less than or equal to 0
  if (num <= 0)
  {num = strlen(str);}

  //Get the character position in i for substring instance to start from
  for (i = 0; str[i] != '\0' ; i++)
   {
     if (strstr(&str[i], subStr) == &str[i])
     {
      count++;
      i += oldlen - 1;
      if (count == beg)
      {break;}
     }
   }

   //Get everything before position i before replacement begins

   x = 0;
   while (i != x)
   {  result[x++] = *str++; }

  //Start replacement
   while (*str) //for the complete input string
   {

    if (num != 0 ) // untill no more occurances need to be changed
    {
       if (strstr(str, subStr) == str )
       {
          strcpy(&result[x], rep);
          x += newlen;
          str += oldlen;
          num--;
       }
       else // if no match is found
       {
          result[x++] = *str++;
       }
    }
    else
    {
       result[x++] = *str++;
    }
   }

    result[x] = '\0'; //Terminate the string
    return result; //Return the replaced string
    free(result);   //free memory
}