#include <bits/stdc++.h>
#define fi first
#define se second
#define ll long long
#define dl double long
using namespace std;
const int N = 1e6 + 7;
const int M = 107;
const ll mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int n;
ll a[N];
ll s[N];
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
//freopen( "input.txt" , "r" , stdin );
//freopen( "output.txt" , "w" , stdout );
cin >> n;
ll mx = 0 , mn = 0;
for( int i = 2; i <= n; i++ ){
cin >> a[i];
s[i] = s[i - 1] + a[i];
mx = max( mx , s[i] );
mn = min( mn , s[i] );
}
if( mn <= -n || mx >= n || 1 - mn != n - mx ){
cout << "-1";
return 0;
}
ll st = 1 - mn;
cout << st << " ";
for( int i = 2; i <= n; i++ ){
cout << st + s[i] << " ";
}
}
