cishu总是为零

#include<stdio.h>
#define N 100

int main()
{
    char a[N],b[N];
    printf("字符串:\n");
    gets(a);
    printf("子字符串:\n");
    gets(b);
    value(a,b);

    return 0;
}

void value(char a[],char b[])
{
    int i,j,k,geshu=0;
    int *p,*q;
    for(i=0; a[i]!='\0'; i++)
    {
        if(a[i]==b[0])
        {
            p=&a[i];
            q=&b[0];
            while((*p==*q)&&(*q!='\0'))
            {
                p++;
                q++;
            }
            if(*q=='\0')
            {
                cishu++;
            }
        }
    }

    printf("子字符串%s出现次数:\n%d",b,cishu);
}

那为什么cishu总是为零啊