#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
ll max(ll x, ll y) { return x > y ? x : y; }
ll min(ll x, ll y) { return x < y ? x : y; }
ll gcd(ll x, ll y) {
if (y == 0) return x;
return gcd(y, x % y);
}
ll lcm(ll x, ll y) { return x * y / gcd(x, y); }
#define f(i, m, n) for (ll i = (ll)m; i < (ll)n; i++)
#define f_(i, n, m) for (ll i = (ll)n; i >= (ll)m; i--)
#define fa(i, x) for (auto i : x)
#define vll vector<ll>
#define vvll vector<vll>
#define vvvll vector<vvll>
#define vb vector<bool>
#define vvb vector<vb>
#define pll pair<ll, ll>
#define ff first
#define ss second
#define vpll vector<pll>
#define all(x) x.begin(), x.end()
#define vvpll vector<vpll>
#define um unordered_map
#define us unordered_set
#define ms multiset
#define pqllMaxHeap priority_queue<ll>
#define pqllMinHeap priority_queue<ll, vector<ll>, greater<ll>>
#define pqpll priority_queue<pll, vector<pll>, greater<pll>>
#define pq(x) priority_queue<x, vector<x>, greater<x>>
#define ub upper_bound
#define lb lower_bound
#define pb push_back
#define acc accumulate
#define in insert
#define clr clear
#define nl cout << "\n";
const ll M = 1e9 + 7;
const ll M1 = 998244353;
const ll inf = 1e18 + 10;
const ll inf_ = -1e18 - 10;
const int N = 300005;
void solve() {
ll n; cin >> n;
vll v;
v.push_back(1);
ll cnt = 1;
for(ll i = 0; i < n - 1; i++){
ll a; cin >> a;
cnt += a;
if (i == 0 && a == 0){
cout << -1 << endl;
return;
}
v.push_back(cnt);
}
f(i, 0, n) cout << v[i] << " ";
cout << endl;
}
bool multi = 0;
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
int t = 1;
if (multi) cin >> t;
while (t--) solve();
return 0;
}
