#include <iostream>
#include <iomanip>
#include <vector>
#include <cmath>
#include <algorithm>
#include <set>
#include <queue>
#include <map>
#include <stack>
#include <bitset>
#include <string>
#include <cstring>
#include <iterator>
#include <random>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef long double ld;
const ll dim = 2*(1e6)+7;
//const ll mod = 1e9 + 7;
const ll inf = 1e17 + 77;
#define endl "\n"
#define fi first
#define pb push_back
#define se second
#define vll vector<ll>
ll n, m, k;
ll a[dim], dp[dim];
int main() {
ll u, w,q, v, y;
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin>>n;
ll mn=n;
ll mx=0;
ll sm=0;
for(int i=1; i<=n-1; i++){
cin>>a[i];
sm+=a[i];
mn=min(mn, sm);
mx=max(mx, sm);
}
ll l=1;
ll r=n;
l=max<ll>(1, 1-mn);
r=min(n, n-mx);
if(l==r){
sm=l;
cout<<l<<" ";
for(int i=1; i<=n-1; i++){
sm+=a[i];
cout<<sm<<" ";
}
cout<<endl;
}
else{
cout<<-1<<endl;
}
return 0;
}
