#include<iostream>
#include<vector>
#include<cmath>
#include<algorithm>
#include<climits>
#include<set>
#include<map>
#define ll long long int
using namespace std;
void solve();
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int t = 1;
//cin>>t;
while(t--) {
solve();
cout<<"\n";
}
return 0;
}
void solve() {
int n;
cin>>n;
int min1 = 0;
int max1 = 0;
int count = 0;
vector<int> arr(n,0);
for(int i = 0; i < n - 1; i++) {
cin>>arr[i];
count += arr[i];
max1 = max(max1,count);
min1 = min(min1,count);
}
if ((max1 - min1) != n - 1) {
cout << -1;
return;
}else{
int num = 1 - min1;
for(int i = 0; i < n; i++) {
cout << num << " ";
num += arr[i];
}
}
}
