Submission #394445

#	Time	Username	Problem	Language	Result	Execution time	Memory
394445		teehandsome	Race (IOI11_race)	C++11	21 / 100	3078 ms	11068 KiB

race

#include "race.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define INF 1e9+7
#define all(x) x.begin(),x.end()
using namespace std;
using namespace __gnu_pbds;
using ll=long long;
using pii=pair<int,int>;
using ppi=pair<int,pii>;
using oset=tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>;

template<typename T>
void _print(vector<T> x) {cerr<<"{"; for(auto e:x) cerr<<e<<","; cerr<<"}";}
void _print(pii x) {cerr<<"{"<<x.first<<","<<x.second<<"}";}
template<typename T>
void _print(T x) {cerr<<x;}

void dbg() {cerr<<endl;}
template<typename Head,typename... Tail>
void dbg(Head H,Tail... T) {
    _print(H);
    if(sizeof...(T)) cerr<<",";
    else cerr<<"\"]";
    dbg(T...);
}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:[\"",dbg(__VA_ARGS__)

//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int mxn=2e5+10;
int n,k;
vector<pii> adj[mxn];

int solve(int u,int p,int sum) {
    if(!sum) return 0;
    if(sum<0) return -1;
    int res=INF;
    for(auto vw:adj[u]) {
        int v=vw.first, w=vw.second;
        if(v==p) continue;
        int temp=solve(v,u,sum-w);
        if(temp!=-1) res=min(res,1+temp);
    }
    if(res==INF) return -1;
    return res;
}

int best_path(int N, int K, int H[][2], int L[])
{
    n=N,k=K;
    for(int i=0;i<n-1;i++) {
        int u=H[i][0],v=H[i][1],w=L[i];
        adj[u].push_back({v,w});
        adj[v].push_back({u,w});
    }
    int ans=INF;
    for(int i=0;i<n;i++) {
        int temp=solve(i,i,k);
        if(temp!=-1) ans=min(ans,temp);
    }
    if(ans==INF) return -1;
    return ans;
}

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