66_查找函数

//_66_查找函数
//_66_main.cpp

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

char *alpha = "abcdefghijklmnopqrstuvwxyz";
int comp(const void *ch,const void *s);

int main()
{
	printf("Enter a character: ");
	char ch=getchar();
	ch = tolower(ch);//将变元ch转换成小写字符
	char *p = (char *)bsearch(&ch,alpha,26,1,comp);
	if(p)
		printf("%c is in alphabet.\n",*p);
	else
		printf("is not in alphabet.\n");

	system("pause");
	return 0;
}

int comp(const void *ch,const void *s)
{
	return *(char *)ch - *(char *)s;
}