Submission #1574092
Source Code Expand
#include<bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<int, int> ii; typedef pair<int, ii> iii; const int MAX = 2e5+1; bool ok = true; vector<vector<int>> g; vector<ll> a; ll go(int u, int p) { ll sum = 0; bool leaf = true; vector<ll> d(g[u].size()); for(int i = 0; i < g[u].size(); i++) { int v = g[u][i]; if(v != p) { leaf = false; d[i] = go(v, u); sum += d[i]; } } // cout << u << " - " << sum << endl; if(leaf || (p == -1 && g[u].size() == 1)) { if(p == -1) ok &= sum == a[u]; return a[u]; } ll r = 2*a[u] - sum; // cout << u << " " << r << " " << sum << endl; if(p != -1) ok &= r >= 0; if(p != -1) sum += r; ok &= sum == 2*a[u]; ok &= sum % 2 == 0; for(int i = 0; i < g[u].size(); i++) { ok &= d[i] <= sum/2; } ok &= r <= sum/2; return r; } int main() { ios::sync_with_stdio(0); cin.tie(0); #ifdef LOCAL freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); #else #define endl '\n' #endif int n; cin >> n; g.assign(n+1, vector<int>()); a.assign(n+1, 0); for(int i = 1; i <= n; i++) { cin >> a[i]; } for(int i = 1; i < n; i++) { int a, b; cin >> a >> b; g[a].push_back(b); g[b].push_back(a); } go(1, -1); if(ok) cout << "YES" << endl; else cout << "NO" << endl; }
Submission Info
Submission Time | |
---|---|
Task | C - Cleaning |
User | vjudge5 |
Language | C++14 (GCC 5.4.1) |
Score | 700 |
Code Size | 1491 Byte |
Status | AC |
Exec Time | 70 ms |
Memory | 15872 KB |
Judge Result
Set Name | Sample | All | ||||
---|---|---|---|---|---|---|
Score / Max Score | 0 / 0 | 700 / 700 | ||||
Status |
|
|
Set Name | Test Cases |
---|---|
Sample | sample1.txt, sample2.txt, sample3.txt |
All | sample1.txt, sample2.txt, sample3.txt, in1.txt, in10.txt, in11.txt, in12.txt, in13.txt, in14.txt, in15.txt, in16.txt, in17.txt, in18.txt, in19.txt, in2.txt, in20.txt, in21.txt, in22.txt, in23.txt, in24.txt, in25.txt, in26.txt, in27.txt, in28.txt, in29.txt, in3.txt, in30.txt, in31.txt, in32.txt, in33.txt, in34.txt, in35.txt, in36.txt, in37.txt, in38.txt, in39.txt, in4.txt, in40.txt, in41.txt, in42.txt, in43.txt, in44.txt, in45.txt, in5.txt, in6.txt, in7.txt, in8.txt, in9.txt, sample1.txt, sample2.txt, sample3.txt |
Case Name | Status | Exec Time | Memory |
---|---|---|---|
in1.txt | AC | 49 ms | 6656 KB |
in10.txt | AC | 53 ms | 6656 KB |
in11.txt | AC | 54 ms | 14080 KB |
in12.txt | AC | 51 ms | 14080 KB |
in13.txt | AC | 49 ms | 15872 KB |
in14.txt | AC | 47 ms | 14592 KB |
in15.txt | AC | 1 ms | 256 KB |
in16.txt | AC | 1 ms | 256 KB |
in17.txt | AC | 1 ms | 256 KB |
in18.txt | AC | 1 ms | 256 KB |
in19.txt | AC | 48 ms | 6656 KB |
in2.txt | AC | 47 ms | 6656 KB |
in20.txt | AC | 48 ms | 6656 KB |
in21.txt | AC | 48 ms | 6656 KB |
in22.txt | AC | 48 ms | 6656 KB |
in23.txt | AC | 47 ms | 6656 KB |
in24.txt | AC | 62 ms | 6656 KB |
in25.txt | AC | 1 ms | 256 KB |
in26.txt | AC | 49 ms | 6656 KB |
in27.txt | AC | 49 ms | 6656 KB |
in28.txt | AC | 1 ms | 256 KB |
in29.txt | AC | 44 ms | 6656 KB |
in3.txt | AC | 45 ms | 6656 KB |
in30.txt | AC | 1 ms | 256 KB |
in31.txt | AC | 49 ms | 6656 KB |
in32.txt | AC | 47 ms | 6656 KB |
in33.txt | AC | 48 ms | 6656 KB |
in34.txt | AC | 47 ms | 6656 KB |
in35.txt | AC | 49 ms | 6656 KB |
in36.txt | AC | 47 ms | 6656 KB |
in37.txt | AC | 2 ms | 384 KB |
in38.txt | AC | 70 ms | 6656 KB |
in39.txt | AC | 45 ms | 6656 KB |
in4.txt | AC | 49 ms | 6656 KB |
in40.txt | AC | 45 ms | 6656 KB |
in41.txt | AC | 48 ms | 6656 KB |
in42.txt | AC | 61 ms | 6656 KB |
in43.txt | AC | 47 ms | 6656 KB |
in44.txt | AC | 48 ms | 6656 KB |
in45.txt | AC | 48 ms | 6656 KB |
in5.txt | AC | 47 ms | 6656 KB |
in6.txt | AC | 50 ms | 6656 KB |
in7.txt | AC | 44 ms | 5888 KB |
in8.txt | AC | 12 ms | 1792 KB |
in9.txt | AC | 48 ms | 6656 KB |
sample1.txt | AC | 1 ms | 256 KB |
sample2.txt | AC | 1 ms | 256 KB |
sample3.txt | AC | 1 ms | 256 KB |