no_space.c

#include <stdlib.h>

int no_space_strlen(const char *s) {

  int len, j;

  len = j = 0;
  while (s[len] != '\0') {
    if (s[len] == ' ')
      j++;
    len++;
  }
  return (len - j);
}

char *no_space(const char *str_in) {

  char *space_free;
  int i, j;
  i = j = 0;
  space_free = (char *)malloc(sizeof(char) * no_space_strlen(str_in) + 1);
  while(str_in[i] != '\0' && space_free != NULL) {
    if(str_in[i] != ' ') {
      space_free[j] = str_in[i];
      j++;
    }
    i++;
  }
  space_free[j] = '\0';
  return (space_free);
}