我好像想复杂了……

……

#include <bits/stdc++.h>
using namespace std;
int index(int a[], int len, int num)
{
    int index;
    for(int i = 0; i < len; i++)
        {
            if(a[i] == num)
                return i + 1;
        }
}
int main()
{
    int arr[7], sad = 0, max = 0;
    for(int i = 0; i < 7; i++)
        {
            int school, home;
            cin >> school >> home;
            arr[i] = school + home;
        }
    for(int i = 0; i < 7; i++)
        {
            if(arr[i] > 8)
                sad = 1;
            if(arr[i] > max)
                max = arr[i];
        }
    if(sad)
        cout << index(arr, 7, max);
    else
        cout << 0;
    return 0;
}