#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2e5 + 10;
const int MOD = 1e9 + 7;
int n;
long long int a[MAXN], minn;
bool have[MAXN], flag;
int main() {
  while (scanf("%d", &n) != EOF) {
    a[1] = 0;
    minn = 0;
    memset(have, false, sizeof(have));
    flag = true;
    for (int i = 1; i < n; ++i) {
      int num;
      scanf("%I64d", &num);
      a[i + 1] = a[i] + num;
      minn = min(minn, a[i + 1]);
    }
    for (int i = 1; i <= n; ++i) {
      a[i] += -minn + 1;
      if (a[i] > n || have[a[i]]) {
        printf("-1\n");
        flag = false;
        break;
      }
      have[a[i]] = true;
    }
    if (flag) {
      for (int i = 1; i <= n; ++i) {
        i == n ? printf("%I64d\n", a[i]) : printf("%I64d ", a[i]);
      }
    }
  }
  return 0;
}
