#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <ll, ll> pii;
#define fi first
#define se second
#define pb push_back
const int MOD = 1e9;
const int MAX = 3e5 + 5;
const int dx[4] = {0, 0, 1, -1};
const int dy[4] = {1, -1, 0, 0};
#define int ll
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n; cin >> n;
int a[n + 5];
for(int i = 1 ; i < n ; i++)cin >> a[i];
int mx = 0, mn = 0;
int cur = 0;
vector <int> v;v.pb(0);
for(int i = 1 ; i < n ; i++){
cur += a[i];
v.pb(cur);
mx = max(mx, cur);
mn = min(mn, cur);
}
if(mx - mn != n)cout << -1 << endl;
else{
map <int, int> mp;
for(int i = mn ; i <= mx ; i++)mp[i] = i - mn + 1;
for(auto it : v)cout << mp[it] << ' ';
cout << endl;
}
return 0;
}
