#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,a,b) for(int i=a;i<=b;++i)
#define per(i,a,b) for(int i=a;i>=b;--i)
#define pb push_back
const int MAXN=3e5 + 10;
int a[MAXN], b[MAXN];
int32_t main(){
ios::sync_with_stdio(0);cin.tie(0);
int n;cin >> n;
rep(i,2,n) cin >> a[i];
int l=1,r=n, s = 0;
rep(i,2,n) {
s += a[i];
if (s < 0) l = max(l,1-s);
else r = min(r,n-s);
}
if (l!=r) {
cout << "-1\n";
return 0;
}
b[1] = l;
rep(i,2,n) b[i] = b[i-1]+a[i];
rep(i,1,n) cout << b[i] << " \n"[i==n];
return 0;
}
