probleme cu siruri de numere

#include <iostream>

using namespace std;

int main() {
    int n, a[1001],maxx=0,minn=99999999,sum=0; ///max 1000 de elemente
    double medie;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        if(a[i]>maxx){
            maxx=a[i];
        }
    }
    cout<<maxx;
    for(int i=1;i<=n;i++){
        if(a[i]<minn){
            minn=a[i];
        }

    }
    cout<<endl;
    cout<<minn;
    for(int i=1;i<=n;i++){
        sum=a[i]+sum;
    }
    cout<<endl;
    cout<<sum;
    medie = 1.0*sum /n;
    cout<<endl<<medie;
    return 0;
}