#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, q[200050], p[200050], vis[200050];
  while (~scanf("%lld", &n)) {
    memset(vis, 0, sizeof(vis));
    long long int cnt = 0;
    int acm = 1;
    long long int sum = 0, maxx = 0;
    long long int pos = 1;
    for (int i = 1; i <= n - 1; i++) {
      scanf("%lld", &q[i]);
      sum += q[i];
      if (sum > maxx) {
        maxx = sum;
        pos = i + 1;
      }
    }
    if (pos >= 1 && pos <= n) {
      p[pos] = n;
      cnt++;
      vis[n] = 1;
    } else {
      acm = 0;
    }
    if (acm) {
      for (long long int i = pos - 1; i >= 1; i--) {
        p[i] = p[i + 1] - q[i];
        if (p[i] >= 1 && p[i] <= n && !vis[p[i]]) {
          cnt++;
          vis[p[i]] = 1;
        } else {
          acm = 0;
          break;
        }
      }
      if (acm) {
        for (long long int i = pos + 1; i <= n; i++) {
          p[i] = p[i - 1] + q[i - 1];
          if (p[i] >= 1 && p[i] <= n && !vis[p[i]]) {
            cnt++;
            vis[p[i]] = 1;
          } else {
            acm = 0;
            break;
          }
        }
      }
    }
    if (acm && cnt == n) {
      for (int i = 1; i < n; i++) printf("%lld ", p[i]);
      printf("%lld\n", p[n]);
    } else
      printf("-1\n");
  }
}
