#include <iostream>
#include <math.h>
#include <vector>
#include <string>
#include <algorithm>
#include <queue>
#include <stack>
#include <map>
#include <cstring>
#include <iomanip>
#include <set>
#include <bitset>
#include <unordered_map>
#include <cstdlib>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using piii = tuple<int,int,int>;
#define f first
#define s second
#define endl '\n'
#define all(x) begin(x),end(x)
int const INF = 1e9+10;
int main(){
int n;cin >> n;
vector<int> vc = {1};
int cur = 1;
int mini = 1;
int maxi = 1;
for(int i{1};i < n;i++){
int g;cin >> g;
vc.emplace_back(vc.back()+g);
mini = min(vc.back(),mini);
maxi = max(vc.back(),maxi);
}
int add = 1-mini;
if(maxi+add == n){
for(auto k:vc) cout << k+add << " ";
}
else cout << -1;
}
