C program to eliminate white spaces from string

Write a C program to eliminate white spaces from the given string.

  #include <stdio.h>
  #include <string.h>

  int main() {
        char str[256], *ptr1, *ptr2;

        /* get the input string from the user */
        printf("Enter your input string:");
        fgets(str, 256, stdin);
        str[strlen(str) - 1] = '\0';

        /* ptr1 and ptr2 points to 1st character of i/p string */
        ptr1 = ptr2 = str;

        /* copy all characters in the i/p string except space */
        while (*ptr1 != '\0') {

                /* skip the space */
                if (*ptr1 == ' ') {
                        ptr1++;
                        continue;
                }

                /* copy characters alone */
                *ptr2++ = *ptr1++;
        }

        /* null termination */
        *ptr2 = *ptr1;

        /* printing the result */
        printf("Resultant String: %s\n", str);
        return 0;
  }

  Output:

  jp@jp-VirtualBox:~/$ ./a.out
  Enter your input string:ignore white space in input string
  Resultant String: ignorewhitespaceininputstring