比较两个字符串的大小

#include<stdio.h>
int strcmp(char *p1, char *p2)
{
    int i = 0, n = 0;
    while (*p1 == *p2) { p1++; p2++; }
    n = *p1 - *p2;
    if(n>25||n<-25)return 0;
    else return n;
}
void input(char *p1,char *p2)
{
    gets(p1);gets(p2);
}
int main()
{
    char s1[100], s2[100]; 
    input(s1,s2);
    printf("%d", strcmp(s1, s2));
    return 0;
}