#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e17 + 10;
const int N = 1e6 + 10;
const long long mod = 1e9 + 7;
const int base = 131;
const double pi = acos(-1);
map<string, int> ml;
map<long long, long long> mp;
map<int, int> vi;
long long b[N], vis[N], visrow[N], viscol[N], dep[N], num[N], a[N], n, m, k, x,
    y;
long long ex, ey, t, cnt, cnt2, ans, sum, flag;
long long nex[N];
vector<int> fac[N], A, B, C, D;
map<int, int> dp[N];
set<long long> first, second;
string s, ss;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n;
  for (int i = 1; i < n; i++) {
    cin >> a[i];
    b[i] = a[i] + b[i - 1];
  }
  long long mx = 0;
  for (int i = 1; i < n; i++) {
    if (b[i] > mx) {
      mx = b[i];
      k = i + 1;
    }
  }
  b[k] = n;
  for (int i = k + 1; i <= n; i++) {
    b[i] = b[i - 1] + a[i - 1];
  }
  for (int i = k - 1; i >= 1; i--) {
    b[i] = b[i + 1] - a[i];
  }
  for (int i = 1; i <= n; i++) {
    mp[b[i]]++;
    if (mp[b[i]] >= 2 || b[i] > n || b[i] <= 0) return cout << -1 << endl, 0;
  }
  for (int i = 1; i <= n; i++) cout << b[i] << " ";
}
