为什么第一个点会错

#include<bits/stdc++.h>
using namespace std;
long long n,s1,s2,sum=0,num,a,b,k;
char s[100][20],c1,c2;
int main()
{
    int max=0; 
    cin>>n;
    for(int i=0;i<n;i++)
    {
        cin>>s[i]>>s1>>s2>>c1>>c2>>num;
        a=c1=='Y'? 1:0;
        b=c2=='Y'? 1:0;
        int cnt=0;
        if(s1>80&&num>0) cnt+=8000;
        if(s1>85&&s2>80) cnt+=4000;
        if(s1>90) cnt+=2000;
        if(b&&s1>85) cnt+=1000;
        if(a&&s2>80) cnt+=850;
        sum+=cnt;
        if(cnt>max) {max=cnt;k=i;}
    }
    cout<<s[k]<<endl<<max<<endl<<sum;
    return 0;
}