C. Polycarp Restores Permutation Codeforces Round #547 (Div. 3)

Codeforces Round #547 (Div. 3)

#include <bits/stdc++.h>
#define ll long long
using namespace std;
int n,m;
map<int,int> mp;
ll pre[200005],s[200005],a[200005];
 
int main()
{
  scanf("%d",&n);
  for(int i=1;i<n;i++){
    scanf("%lld",&pre[i]);
  }
  ll ans = 0;
  for(int i=1;i<n;i++){
    s[i] = pre[i] + s[i-1];// S[i] = Pi - P1
    ans += s[i]; // ans 是 Pn+Pn-1+Pn-2+...+P2 - (n - 1)*P1
  }
  a[1] = (ll)n * (ll)(n + 1) / 2 - ans; // 这样a[1] = n * P1
  a[1] /= n; //得到P1就得到答案了
  mp[a[1]] ++;
  for(int i=1;i<n;i++){
    a[i + 1] = a[i] + pre[i];
    mp[a[i+1]] ++;
  }
  for(int i=1;i<=n;i++){
    if(mp[i] != 1){
      puts("-1");
      return 0;
    }
  }
  for(int i=1;i<=n;i++){
    printf("%lld ",a[i]);
  }
  return 0;
}