为什么50分，求指导

#include<cstdio>
#include<iostream>
using namespace std;
char a[6],b[6];
int sum=1,num=1;
int main()
{
    scanf("%s %s",&a,&b);
    for(int i=0;i<=5;i++)
    {
        //cout<<a[i]-'A'+1<<" ";
        sum*=a[i]-'A'+1;
        num*=b[i]-'A'+1;
    }
    if(sum%47==num%47)cout<<"GO";
    else cout<<"STAY";
    //cout<<sum;
    return 0;
}