C语言实例66：查找函数

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

char *alpha = "abcdefghikjklmnopqrstuvwxyz";

int comp(const void *ch, const void *s);

int main(int argc, char *argv[])
{
    char ch;
    char *p;

    printf("Enter a character: ");
    ch = getchar();
    ch = tolower(ch);
    p = (char *)bsearch(&ch, alpha, 26, 1, comp);
    if(p)
        printf("%c is in alphabet\n", *p);

    system("pause");
    return 0;
}

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