求助

#include<iostream>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<cmath>
using namespace std;
int mmax,sum,n;
struct student
{
    char name;
    int chinese,maths,english,num;  
}a[1005];
int main()
{
    cin>>n;
    for(int i=1; i<=n; i++)
    {
        cin>>a[i].name>>a[i].chinese>>a[i].maths>>a[i].english;
        a[i].num=a[i].chinese+a[i].maths+a[i].english;
        if(a[i].num>mmax)
        {
            sum=i;
            mmax=a[i].num;
        }
    }
    cout<<a[sum].name<<a[sum].chinese<<a[sum].maths<<a[sum].english;
}