USACO Your Ride Is Here

熟悉USACO格式用題目。
每乘一次就做一次mod會比較好。

/*
ID: mythnc2
LANG: C
TASK: ride
*/
#include <stdio.h>
 
#define MAXARY 10
 
int product(char *);
 
int main(void)
{
    FILE *fin, *fout;
    char comet[MAXARY], group[MAXARY];
 
    fin = fopen("ride.in", "r");
    fout = fopen("ride.out", "w");
 
    fscanf(fin, "%s\n", comet);
    fscanf(fin, "%s\n", group);
 
    if (product(comet) == product(group))
        fprintf(fout, "GO\n");
    else
        fprintf(fout, "STAY\n");
    return 0;
}
 
/* product: return the product mod 47 of letters */
int product(char *ary)
{
    int p;
 
    p = 1;
    while (*ary) {
        p *= (*ary - 'A' + 1);
        p %= 47;
        ary++;
    }
    return p;
}