tcpl-ex-5-4.c

/*
 * Exercise 5-4. Write the function strend(s,t), which returns 1 if the 
 * string t occurs at the end of the string s, and zero otherwise.  
 */

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

int strend(char *s, char *t)
{
	int slen = strlen(s);
	int tlen = strlen(t);
	int i, j;
	for (i = slen - 1, j = tlen - 1; i >= 0 && j >=0 && *(s + i) == *(t + j); i--, j--)
		;
	if (j < 0)
		return 1;
	else
		return 0;
}

int main(void)
{
  char *s1 = "some really long string.";
  char *s2 = "ng.";
  char *s3 = "ng";
 
  if(strend(s1, s2))
  {
    printf("The string (%s) has (%s) at the end.\n", s1, s2);
  }
  else
  {
    printf("The string (%s) doesn't have (%s) at the end.\n", s1, s2);
  }
  if(strend(s1, s3))
  {
    printf("The string (%s) has (%s) at the end.\n", s1, s3);
  }
  else
  {
    printf("The string (%s) doesn't have (%s) at the end.\n", s1, s3);
  }
 
  return 0;
}