oj.uz

답안 #716953

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
716953 2023-03-31T13:38:28 Z Dan4Life Museum (CEOI17_museum) C++17
20 / 100
 3000 ms 785788 KB 
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
const int mxN=(int)1e4+10;
const int LINF = (int)1e9;
int n, k, s, sub[mxN];
vector<pair<int,int>> adj[mxN];
int dp[mxN][mxN][2], dp2[mxN][mxN][2];

int findSize(int s, int p){
	sub[s]=1;
	for(auto [u,w] : adj[s])
		if(u!=p) sub[s]+=findSize(u,s);
	return sub[s];
}

void dfs(int s, int p){
	vector<pair<int,int>> v; v.clear();
	for(auto [u,w] : adj[s])
		if(u!=p) dfs(u,s), v.pb({u,w});
	dp[s][1][0]=dp[s][1][1]=0;
	if(!sz(v)) return;
	for(int i = 0; i <= sz(v); i++)
		for(int j = 0; j <= sub[s]; j++)
			dp2[i][j][0]=dp2[i][j][1]=LINF;
	dp2[0][0][0] = dp2[0][0][1] = 0; int tot = 0;
	for(int i = 1; i <= sz(v); i++){
		auto u = v[i-1].se; tot+=sub[u];
		for(int j = 0; j <= sub[s]; j++){
			for(int x = 0; x < 2; x++){
				dp2[i][j][x] = min(dp2[i][j][x],dp2[i-1][j][x]);
				for(int l = 1; l <= sub[s]; l++){
					dp2[i][j+l][x] = min(dp2[i][j+l][x], dp2[i-1][j][x]+dp[v[i-1].fi][l][1]+2*u);
					if(!x) dp2[i][j+l][x] = min(dp2[i][j+l][x], dp2[i-1][j][1]+dp[v[i-1].fi][l][0]+u);
				}
			}
		}
	}
	for(int i = 2; i <= sub[s]; i++)
		for(int j = 0; j < 2; j++)
			dp[s][i][j] = min(dp[s][i][j],dp2[sz(v)][i-1][j]);
}
 
int32_t main()
{
    ios_base::sync_with_stdio(false); cin.tie(0);
    cin >> n >> k >> s;
	memset(dp, 63, sizeof(dp));
	for(int i = 1; i < n; i++){
		int a, b, c; cin >> a >> b >> c;
		adj[a].pb({b,c}), adj[b].pb({a,c});
	}
	findSize(s,-1); dfs(s,-1); cout << dp[s][k][0];
}

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 292 ms 784956 KB Output is correct
2 Correct 286 ms 784808 KB Output is correct
3 Correct 286 ms 784836 KB Output is correct
4 Correct 278 ms 784836 KB Output is correct
5 Correct 293 ms 784880 KB Output is correct

Subtask #2
0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3115 ms 785788 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 3115 ms 785788 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 292 ms 784956 KB Output is correct
2 Correct 286 ms 784808 KB Output is correct
3 Correct 286 ms 784836 KB Output is correct
4 Correct 278 ms 784836 KB Output is correct
5 Correct 293 ms 784880 KB Output is correct
6 Execution timed out 3115 ms 785788 KB Time limit exceeded
7 Halted 0 ms 0 KB -