不知道为什么是RE

#include<iostream>
#include<algorithm>
using namespace std;
struct stu{
string name;
int id;
double y,x,e,sum;
}a[105];
bool cmp(stu x,stu y){
if(x.sum != y.sum)
return x.sum> y.sum;
else if(x.y!=y.y)
return x.y>y.y;
else
return x.id<y.id;
}
int main() {
int n;
cin>>n;
for(int i=0;i<n;i++){
cin>>a[i].name>>a[i].y>>a[i].x>>a[i].e;
a[i].id=i;
a[i].sum=a[i].y+a[i].x+a[i].e;
}

sort(a,a+n,cmp);
for(int j=0;j<n;j++){
 cout<<a[j].name<<" "<<a[j].sum<<endl;
}
    return 0;
}