oj.uz

답안 #919118

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
919118 2024-01-31T10:25:21 Z ttamx Mergers (JOI19_mergers) C++14
0 / 100
 51 ms 38344 KB 
#include<bits/stdc++.h>

using namespace std;

const int N=5e5+5;

int n,k;
vector<int> adj[N],comp[N];
int sz[N],hv[N],lv[N],hd[N],pa[N];
int a[N];

void dfs(int u,int p=0){
    pa[u]=p;
    sz[u]=1;
    for(auto v:adj[u])if(v!=p){
        lv[v]=lv[u]+1;
        dfs(v,u);
        sz[u]+=sz[v];
        if(sz[v]>sz[hv[u]])hv[u]=v;
    }
}

void hld(int u,int p=0){
    if(!hd[u])hd[u]=u;
    if(hv[u])hd[hv[u]]=hd[u],hld(hv[u],u);
    for(auto v:adj[u])if(v!=p&&v!=hv[u])hld(v,u);
}

int lca(int u,int v){
    while(hd[u]!=hd[v]){
        if(lv[hd[u]]<lv[hd[v]])swap(u,v);
        u=pa[hd[u]];
    }
    return lv[u]<lv[v]?u:v;
}

void pull(int u,int p=0){
    for(auto v:adj[u])if(v!=p){
        pull(v,u);
        a[u]+=a[v];
    }
}

int main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n >> k;
    for(int i=1;i<n;i++){
        int u,v;
        cin >> u >> v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    for(int i=1;i<=n;i++){
        int x;
        cin >> x;
        comp[x].emplace_back(i);
    }
    dfs(1);
    hld(1);
    for(int i=1;i<=k;i++){
        for(int j=1;j<comp[i].size();j++){
            int u=comp[i][j-1],v=comp[i][j];
            a[u]++,a[v]++,a[lca(u,v)]-=2;
        }
    }
    pull(1);
    int ans=0;
    for(int i=2;i<=n;i++)ans+=a[i]==0;
    cout << (ans+1)/2;
}

Compilation message

mergers.cpp: In function 'int main()':
mergers.cpp:61:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |         for(int j=1;j<comp[i].size();j++){
      |                     ~^~~~~~~~~~~~~~~

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 29272 KB Output is correct
2 Correct 7 ms 29272 KB Output is correct
3 Correct 8 ms 29384 KB Output is correct
4 Correct 8 ms 29272 KB Output is correct
5 Correct 10 ms 29532 KB Output is correct
6 Correct 8 ms 29272 KB Output is correct
7 Correct 7 ms 29272 KB Output is correct
8 Correct 8 ms 29528 KB Output is correct
9 Incorrect 9 ms 29276 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #2
0 / 24.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 29272 KB Output is correct
2 Correct 7 ms 29272 KB Output is correct
3 Correct 8 ms 29384 KB Output is correct
4 Correct 8 ms 29272 KB Output is correct
5 Correct 10 ms 29532 KB Output is correct
6 Correct 8 ms 29272 KB Output is correct
7 Correct 7 ms 29272 KB Output is correct
8 Correct 8 ms 29528 KB Output is correct
9 Incorrect 9 ms 29276 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #3
0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 29272 KB Output is correct
2 Correct 7 ms 29272 KB Output is correct
3 Correct 8 ms 29384 KB Output is correct
4 Correct 8 ms 29272 KB Output is correct
5 Correct 10 ms 29532 KB Output is correct
6 Correct 8 ms 29272 KB Output is correct
7 Correct 7 ms 29272 KB Output is correct
8 Correct 8 ms 29528 KB Output is correct
9 Incorrect 9 ms 29276 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #4
0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 39 ms 36040 KB Output is correct
2 Correct 51 ms 38344 KB Output is correct
3 Incorrect 8 ms 29528 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 29272 KB Output is correct
2 Correct 7 ms 29272 KB Output is correct
3 Correct 8 ms 29384 KB Output is correct
4 Correct 8 ms 29272 KB Output is correct
5 Correct 10 ms 29532 KB Output is correct
6 Correct 8 ms 29272 KB Output is correct
7 Correct 7 ms 29272 KB Output is correct
8 Correct 8 ms 29528 KB Output is correct
9 Incorrect 9 ms 29276 KB Output isn't correct
10 Halted 0 ms 0 KB -