Submission #1097950
Source Code Expand
#include <algorithm> #include <cassert> #include <cfloat> #include <climits> #include <cmath> #include <cstdio> #include <cstdlib> #include <deque> #include <iomanip> #include <iostream> #include <limits> #include <map> #include <queue> #include <set> #include <sstream> #include <stack> #include <string> #include <tuple> #include <vector> #define FOR(i,k,n) for (int (i)=(k); (i)<(n); ++(i)) #define rep(i,n) FOR(i,0,n) #define pb push_back #define all(v) begin(v), end(v) #define debug(x) cerr<< #x <<": "<<x<<endl #define debug2(x,y) cerr<< #x <<": "<< x <<", "<< #y <<": "<< y <<endl using namespace std; typedef long long ll; typedef unsigned long long ull; typedef pair<int, int> pii; typedef vector<int> vi; typedef vector<vector<int> > vvi; typedef vector<ll> vll; typedef vector<vector<ll> > vvll; template<class T> using vv=vector<vector< T > >; vi a; vvi g; vi par; ll evaluation(int u) { if ((int)g[u].size() == 1) { return a[u]; } ll sum_childs = 0; vll childs; for (int v : g[u]) { if (v == par[u]) { continue; } ll tmp = evaluation(v); childs.push_back(tmp); sum_childs += tmp; } sort(all(childs)); ll min_a, max_a; max_a = sum_childs; if (childs.back() * 2 >= sum_childs) { min_a = childs.back(); } else { min_a = (sum_childs + 1) / 2; } if (a[u] < min_a || max_a < a[u]) { printf("NO\n"); exit(0); } return sum_childs - (sum_childs - a[u]) * 2; } void search_main(int root) { ll sum_child = 0; vll childs; for (int u : g[root]) { ll tmp = evaluation(u); childs.push_back(tmp); sum_child += tmp; } if (a[root] * 2 != sum_child) { printf("NO\n"); exit(0); } sort(all(childs)); if (childs.back() * 2 > sum_child) { printf("NO\n"); exit(0); } } int main() { int n; scanf("%d", &n); a.resize(n); rep (i, n) { scanf("%d", &a[i]); } g.resize(n); rep (i, n-1) { int u, v; scanf("%d %d", &u, &v); u -= 1; v -= 1; g[u].push_back(v); g[v].push_back(u); } if (n == 2) { if (a[0] == a[1]) { printf("YES\n"); } else { printf("NO\n"); } return 0; } int root = 0; rep (i, n) { if (g[root].size() < g[i].size()) { root = i; } } par.resize(n); par[root] = root; deque<int> st; for (int u : g[root]) { par[u] = root; st.push_back(u); } while (!st.empty()) { int u = st.front(); st.pop_front(); for (int v : g[u]) { if (v == par[u]) { continue; } par[v] = u; st.push_back(v); } } search_main(root); printf("YES\n"); return 0; }
Submission Info
Submission Time | |
---|---|
Task | C - Cleaning |
User | tspcx |
Language | C++14 (Clang 3.8.0) |
Score | 700 |
Code Size | 2773 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 |
Case Name | Status | Exec Time | Memory |
---|---|---|---|
in1.txt | AC | 62 ms | 6912 KB |
in10.txt | AC | 61 ms | 6656 KB |
in11.txt | AC | 70 ms | 14080 KB |
in12.txt | AC | 70 ms | 14080 KB |
in13.txt | AC | 68 ms | 15872 KB |
in14.txt | AC | 67 ms | 14592 KB |
in15.txt | AC | 3 ms | 256 KB |
in16.txt | AC | 3 ms | 256 KB |
in17.txt | AC | 3 ms | 256 KB |
in18.txt | AC | 3 ms | 256 KB |
in19.txt | AC | 57 ms | 6656 KB |
in2.txt | AC | 61 ms | 6656 KB |
in20.txt | AC | 54 ms | 6656 KB |
in21.txt | AC | 54 ms | 6656 KB |
in22.txt | AC | 56 ms | 6656 KB |
in23.txt | AC | 58 ms | 6656 KB |
in24.txt | AC | 56 ms | 6656 KB |
in25.txt | AC | 3 ms | 256 KB |
in26.txt | AC | 55 ms | 6656 KB |
in27.txt | AC | 55 ms | 6656 KB |
in28.txt | AC | 3 ms | 256 KB |
in29.txt | AC | 51 ms | 6656 KB |
in3.txt | AC | 62 ms | 6656 KB |
in30.txt | AC | 3 ms | 256 KB |
in31.txt | AC | 62 ms | 6656 KB |
in32.txt | AC | 61 ms | 6656 KB |
in33.txt | AC | 61 ms | 6656 KB |
in34.txt | AC | 61 ms | 6656 KB |
in35.txt | AC | 58 ms | 6656 KB |
in36.txt | AC | 55 ms | 6656 KB |
in37.txt | AC | 3 ms | 384 KB |
in38.txt | AC | 62 ms | 6656 KB |
in39.txt | AC | 61 ms | 6656 KB |
in4.txt | AC | 62 ms | 6656 KB |
in40.txt | AC | 60 ms | 6656 KB |
in41.txt | AC | 61 ms | 6656 KB |
in42.txt | AC | 61 ms | 6656 KB |
in43.txt | AC | 57 ms | 6656 KB |
in44.txt | AC | 57 ms | 6656 KB |
in45.txt | AC | 61 ms | 6656 KB |
in5.txt | AC | 61 ms | 6656 KB |
in6.txt | AC | 61 ms | 6656 KB |
in7.txt | AC | 55 ms | 6016 KB |
in8.txt | AC | 16 ms | 1792 KB |
in9.txt | AC | 61 ms | 6656 KB |
sample1.txt | AC | 3 ms | 256 KB |
sample2.txt | AC | 3 ms | 256 KB |
sample3.txt | AC | 3 ms | 256 KB |