#include <iostream>
#include <vector>
#include <algorithm>
#include <random>
#include <queue>
using namespace std;
typedef long long ll;
const int INF = 1e9;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
vector<int> a = { 1 };
for (int i = 0; i < n - 1; ++i) {
int d;
cin >> d;
a.push_back(a.back() + d);
}
int diff = 1 - *min_element(a.begin(), a.end());
for (int& i : a) {
i += diff;
}
if (*min_element(a.begin(), a.end()) == 1 && *max_element(a.begin(), a.end()) == n) {
for (int i : a) {
cout << i << ' ';
}
cout << '\n';
} else {
cout << -1 << '\n';
}
}
