Submission #1106355

#	Time	Username	Problem	Language	Result	Execution time	Memory
1106355		whoknow	Museum (CEOI17_museum)	C++17	0 / 100	77 ms	4028 KiB

museum

#include <bits/stdc++.h>
#define ll long long
#define F first
#define S second
#define MAXN 10005
#define ii pair<int,int>
#define bit(i,j) ((i>>j)&1)
#define sz(i) (int)i.size()
#define endl '\n'
using namespace std;
const int INF = 1e9;
int n, k, st;
vector<ii>g[MAXN];
namespace sub1
{
vector<int> dp[MAXN][2];
vector<int> combine(vector<int>x, vector<int>y,int w)
{
    vector<int>ans(sz(x)+sz(y)-1,INF);
    for(int i=1;i<sz(x);i++)
        for(int j=0;j<sz(y);j++)
            if(i+j<=k)
                ans[i+j]=min(ans[i+j],x[i]+y[j]+w);
    return ans;
}
vector<int>mn(vector<int>x,vector<int>y)
{
    if(sz(x)<sz(y))
    {
        for(int i=0;i<sz(x);i++)
            y[i]=min(x[i],y[i]);
        return y;
    }
    for(int i=0;i<sz(y);i++)
        x[i]=min(x[i],y[i]);
    return x;
}
void dfs(int u, int p, int cost)
{
    dp[u][0]={0,cost};
    dp[u][1]={INF,cost};
    for(ii i : g[u])
    {
        int v = i.F, w = i.S;
        if(v == p)
            continue;
        dfs(v, u, w);
        dp[u][1] = mn(dp[u][1],combine(dp[u][0], dp[v][1],0));
        dp[u][0] = mn(dp[u][0],combine(dp[u][0], dp[v][0],w));
    }
}
void solve()
{
    dfs(st, 0, 0);
    cout<<dp[st][1][k];
}
}
main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> k >> st;
    for(int i = 1; i < n; i++)
    {
        int x, y, z;
        cin >> x >> y >> z;
        g[x].push_back({y, z});
        g[y].push_back({x, z});
    }
    sub1::solve();
}

Compilation message (stderr)

museum.cpp:58:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   58 | main()
      | ^~~~

• Subtask 1: 0 / 20
• Subtask 2: 0 / 25
• Subtask 3: 0 / 35
• Subtask 4: 0 / 20