#include <bits/stdc++.h>
using namespace std;
int modInverse(int a, int m) {
  int m0 = m;
  int y = 0, x = 1;
  if (m == 1) return 0;
  while (a > 1) {
    int q = a / m;
    int t = m;
    m = a % m, a = t;
    t = y;
    y = x - q * y;
    x = t;
  }
  if (x < 0) x += m0;
  return x;
}
int main() {
  long long int n;
  cin >> n;
  long long int a[n - 1];
  set<long long int> se;
  long long int t = (n * (n + 1)) / 2;
  long long int s = 0;
  for (long long int i = 0; i < n - 1; i++) {
    cin >> a[i];
    s = s + a[i];
    t = t - s;
  }
  long long int an[n];
  long long int f = t / n;
  an[0] = f;
  long long int ch = 0, ch1 = 0;
  se.insert(an[0]);
  if (an[0] > n || an[0] < 1) {
    ch = 1;
  }
  for (long long int i = 0; i < n - 1; i++) {
    an[i + 1] = a[i] + an[i];
    if (!se.count(an[i + 1])) {
      se.insert(an[i + 1]);
    } else {
      ch1 = 1;
    }
    if (an[i + 1] > n || an[i + 1] < 1) {
      ch = 1;
    }
  }
  if (ch == 1 || ch1 == 1)
    cout << -1;
  else {
    for (long long int i = 0; i < n; i++) {
      cout << an[i] << " ";
    }
  }
}
