Submission #674304

#	Time	Username	Problem	Language	Result	Execution time	Memory
674304		lam	Race (IOI11_race)	C++14	0 / 100	7 ms	14420 KiB

race

#include <bits/stdc++.h>
#define ff first
#define ss second
using namespace std;

const int maxn = 2e5 + 10;
int n,k;
map<int,int> mp[maxn];
int id[maxn],d[maxn];
vector <pair<int,int>> adj[maxn];
int ans[maxn];
void dfs(int x, int p, int depth)
{
    ans[x]=0;
    mp[id[x]][depth]++;
    for (int i=0; i<(int)adj[x].size(); i++)
    {
        int v = adj[x][i].ff; int w=adj[x][i].ss;
        if (v==p) continue;
        dfs(v,x,depth+w);
        if (mp[id[i]].size()<mp[id[x]].size())
        {
            for (pair<int,int> j: mp[id[i]])
            {
                ans[x] += mp[id[x]][k - (j.ff - depth) +depth]*j.ss;
                mp[id[x]][j.ff]+=j.ss;
            }
        }
        else
        {
            for (pair<int,int> j: mp[id[x]])
            {
                ans[x] += mp[id[i]][k - (j.ff - depth) +depth]*j.ss;
                mp[id[i]][j.ff]+=j.ss;
            }
            id[x]=id[i];
        }
    }
}


int best_path(int N, int K, int H[][2], int L[])
{
    n=N; k=K;
    for (int i=1; i<=n; i++) id[i]=i;
    for (int i=0; i<n-1; i++)
    {
        int u=H[i][0]; int v=H[i][1];
        u++; v++;
        adj[u].push_back({v,L[i]});
        adj[v].push_back({u,L[i]});
    }
    dfs(1,1,0);
    int res=0LL;
    for (int i=1; i<=n; i++) res+=ans[i];
  return res;
}

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