Submission #784683

#	Time	Username	Problem	Language	Result	Execution time	Memory
784683		aVe	Race (IOI11_race)	C++14	0 / 100	13 ms	27732 KiB

race

#include <bits/stdc++.h>
#include "race.h"
using namespace std;
#define pb push_back
#define mp make_pair
typedef long long ll;
typedef pair<long long, long long> pll;
typedef pair<int,int> pii;
typedef vector<long long> vl;
typedef vector<int> vi;
const int N = 1e6 + 5;
vector<pii> G[N];
int ans = 1e9, arr[N], tmp[N], sz[N], l[N], r[N], k, mx,n;
bool vis[N];
int get_sz(int node, int p = -1){
	sz[node] = 1;
	for(auto next : G[node]){
		if(next.first != p && !vis[next.first]){
			sz[node] += get_sz(next.first, node);
		}
	}
	return sz[node];
}
int get_centroid(int node, int size, int p = -1){
	for(auto next : G[node]){
		if(next.first == p || vis[next.first])	continue;
		if(sz[next.first] >= size)	return get_centroid(next.first, size, node);
	}
	return node;
}
void cnt(int node, int p, int yes, int sum, int level){
	if(sum > k)	return;
	if(sum == k)	ans = min(ans, level);
	if(yes == 1)	tmp[sum] = min(tmp[sum], level);
	else if(yes) tmp[sum] = 1e9;
	else ans = min(ans, level + tmp[k-sum]);
	for(auto next : G[node]){
		if(next.first != p && !vis[next.first])
			cnt(next.first, node, yes, sum + next.second, level+1);
	}
}
void decompose(int node = 0){
	get_sz(node);
	int c = get_centroid(node, sz[node]/2);
	vis[c] = 1;
	mx = 0;
	for(auto next : G[node]){
		if(!vis[next.first])
			cnt(next.first, c, 0, next.second, 1), cnt(next.first, c, 1, next.second, 1);
	}
	for(auto next : G[node]){
		if(!vis[next.first])
			cnt(next.first, c, 2, next.second, 1);
	}
	for(auto next : G[node]){
		if(!vis[next.first])	decompose(next.first);
	}
}
int best_path(int N, int K, int H[][2], int L[]){
	fill(tmp, tmp+1000000 + 5, 1e9);
	n= N, k = K;
	for(int i = 0; i < N-1; i++){
		G[H[i][1]].pb({H[i][0], L[i]});
		G[H[i][0]].pb({H[i][1], L[i]});
	}
	decompose();
	return (ans == 1e9) ? -1 : ans;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57