Submission #1000861

#	Time	Username	Problem	Language	Result	Execution time	Memory
1000861		Tsog	Race (IOI11_race)	C++14	9 / 100	134 ms	262144 KiB

race

#include "race.h"
#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
 
using namespace std;
 
 
const int INF = INT_MAX;
 
void dfs(int v, int parent, vector<vector<int>>& dp, const vector<vector<pair<int,int>>>& adj , int K) {
	for (auto i = 0u; i < adj[v].size(); ++i) {
        int u = adj[v][i].first;
        int cos = adj[v][i].second;
        
        if (u == parent) {
            continue;
        }
        
        for (int k = cos; k <= K; ++k) { 
            if (dp[v][k - cos] != INF) {
                dp[u][k] = min(dp[u][k], dp[v][k - cos] + 1);
            }
        }
        
        dfs(u, v, dp, adj , K);
    }
}
 
 
int best_path(int N, int K, int H[][2], int L[]) {
    vector<vector<pair<int,int>>> adj(N);
    for (int i = 0; i < N - 1; ++i) {
        int u = H[i][0], v = H[i][1];
        adj[u].push_back(mp(v,L[i]));
        adj[v].push_back(mp(u,L[i]));
    }
    
    vector<vector<int>> dp(N, vector<int>(200001, INF));
    for(int i = 0 ; i < N ; i ++)
    	dp[i][0] = 0;
    
    dfs(0, -1, dp, adj , K);
    
    int result = INF;
    for (int v = 0; v < N; ++v) {
        result = min(result, dp[v][K]);
    }
    
    return (result == INF ? -1 : result);
}

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