oj.uz

답안 #767517

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
767517 2023-06-26T19:54:12 Z bLIC Museum (CEOI17_museum) C++17
45 / 100
 3000 ms 246464 KB 
/**
 *  Author: Anil Byar
**/

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>

// using namespace __gnu_pbds;
using namespace std;

// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define uniq(v) v.erase(unique(all(v)), v.end())
#define ft first
#define sd second
#define pb push_back
#define eb emplace_back

// Source: https://codeforces.com/blog/entry/68809
// { start
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end


typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;

#define dbg if(0)

const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;

void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}

template<class T>
istream& operator>>(istream&in, vector<T>&v){
	for (T& x:v) in>>x;
	return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
	for (T& x:v) out<<x<<' ';
	cout<<'\n';
	return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp
// Read the statement carefully

const int N = 10001;

vii adj[N];
int n, k, x;
vi dp[N][2];

vi combine(vi& a, vi& b){
	vi tmp(sz(a)+sz(b)-1, INF);
	for (int i = 0;i<sz(a);i++) for (int j = 0;j<sz(b);j++){
		tmp[i+j] = min(tmp[i+j], a[i]+b[j]);
	}
	return tmp;
}

void dfs(int node, int par){
	dp[node][0] = dp[node][1] = {0};
	int p = sz(adj[node]);
	int q = sz(dp[node][1]);
	vvi pref(p);

	for (int i = 0;i<sz(adj[node]);i++){
		auto z = adj[node][i];
		adj[z.ft].erase(find(all(adj[z.ft]), make_pair(node, z.sd)));
		dfs(z.ft, node);
		assert(sz(dp[z.ft][0])==sz(dp[z.ft][1]));
		for (int j = 1;j<sz(dp[z.ft][1]);j++) {
			dp[z.ft][1][j] += 2*z.sd;
			dp[z.ft][0][j] += z.sd;
		}
		
		dp[node][1] = combine(dp[node][1], dp[z.ft][1]);
		pref[i] = dp[node][1];
	}
	vi suff = {0};
	vi tmp;
	for (int i = p-1;i>0;i--){
		int y = adj[node][i].ft;
		auto v = combine(pref[i-1], suff);
		tmp = combine(v, dp[y][0]);
		if (sz(dp[node][0])<sz(tmp)) dp[node][0].resize(sz(tmp), INF);
		for (int j = 0;j<sz(tmp);j++){
			dp[node][0][j] = min(dp[node][0][j], tmp[j]);
		}
		suff = combine(suff, dp[y][1]);
	}
	if (p){
		int y= adj[node][0].ft;
		tmp = combine(suff, dp[y][0]);
		if (sz(dp[node][0])<sz(tmp)) dp[node][0].resize(sz(tmp), INF);
		for (int j = 0;j<sz(tmp);j++){
			dp[node][0][j] = min(dp[node][0][j], tmp[j]);
		}
	}
	dp[node][0].pb(0);
	dp[node][1].pb(0);
	for (int i = sz(dp[node][0])-1;i>0;i--) swap(dp[node][0][i], dp[node][0][i-1]);
	for (int i = sz(dp[node][1])-1;i>0;i--) swap(dp[node][1][i], dp[node][1][i-1]);
}

void solve(){
	cin>>n>>k>>x;
	for (int i = 0;i<n-1;i++){
		int u, v, w;cin>>u>>v>>w;
		adj[u].eb(v, w);
		adj[v].eb(u, w);
	}

	dfs(x, -1);
	cout<<dp[x][0][k];
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);


#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
	freopen("input.in", "r", stdin);
	freopen("output.out", "w", stdout);
	freopen("debug.dbg", "w", stderr);
	int tt = clock();
#endif

	int t=1, i = 1;
	// cin>>t;
	while(t--){
		// cout<<"Case #"<<i++<<": ";
		solve();
		cout<<'\n';
	}
#ifndef ONLINE_JUDGE
	cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
	tt = clock();
#endif
}

Compilation message

museum.cpp: In function 'void dfs(int, int)':
museum.cpp:112:6: warning: unused variable 'q' [-Wunused-variable]
  112 |  int q = sz(dp[node][1]);
      |      ^
museum.cpp: In function 'int main()':
museum.cpp:180:11: warning: unused variable 'i' [-Wunused-variable]
  180 |  int t=1, i = 1;
      |           ^

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 980 KB Output is correct
2 Correct 1 ms 980 KB Output is correct
3 Correct 1 ms 980 KB Output is correct
4 Correct 1 ms 980 KB Output is correct
5 Correct 1 ms 980 KB Output is correct

Subtask #2
25.0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Correct 119 ms 5452 KB Output is correct
2 Correct 120 ms 6040 KB Output is correct
3 Correct 284 ms 189932 KB Output is correct
4 Correct 172 ms 65864 KB Output is correct
5 Correct 137 ms 18440 KB Output is correct

Subtask #3
0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Correct 119 ms 5452 KB Output is correct
2 Correct 120 ms 6040 KB Output is correct
3 Correct 284 ms 189932 KB Output is correct
4 Correct 172 ms 65864 KB Output is correct
5 Correct 137 ms 18440 KB Output is correct
6 Correct 203 ms 4248 KB Output is correct
7 Correct 225 ms 109492 KB Output is correct
8 Execution timed out 3041 ms 246464 KB Time limit exceeded
9 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 980 KB Output is correct
2 Correct 1 ms 980 KB Output is correct
3 Correct 1 ms 980 KB Output is correct
4 Correct 1 ms 980 KB Output is correct
5 Correct 1 ms 980 KB Output is correct
6 Correct 119 ms 5452 KB Output is correct
7 Correct 120 ms 6040 KB Output is correct
8 Correct 284 ms 189932 KB Output is correct
9 Correct 172 ms 65864 KB Output is correct
10 Correct 137 ms 18440 KB Output is correct
11 Correct 203 ms 4248 KB Output is correct
12 Correct 225 ms 109492 KB Output is correct
13 Execution timed out 3041 ms 246464 KB Time limit exceeded
14 Halted 0 ms 0 KB -