Submission #887397

#	Time	Username	Problem	Language	Result	Execution time	Memory
887397		amirhoseinfar1385	Cats or Dogs (JOI18_catdog)	C++17	38 / 100	3034 ms	7096 KiB

catdog

#include "catdog.h"
#include<bits/stdc++.h>
using namespace std;
const int maxn=100000+10;
vector<int>adj[maxn];
int val[maxn],n,inf=1e6+5;
void pre(int u,int par=0){
    int j=-1;
    for(int i=0;i<(int)adj[u].size();i++){
        if(adj[u][i]!=par){
            pre(adj[u][i],u);
        }
        else{
            j=i;
        }
    }
    if(j>=0){
        adj[u].erase(adj[u].begin()+j);
    }
    return ;
}

pair<int,int>cal(int u){
    vector<pair<int,int>>ret;
    for(auto x:adj[u]){
        ret.push_back(cal(x));
    }
    int red=0,blue=0;
    for(int i=0;i<(int)ret.size();i++){
        red+=min(ret[i].first,ret[i].second+1);
        blue+=min(ret[i].first+1,ret[i].second);
    }
    if(val[u]==0){
        return make_pair(red,blue);
    }
    else if(val[u]==1){
        return make_pair(red,red+1);
    }
    else{
        return make_pair(blue+1,blue);
    }
}

void initialize(int N, std::vector<int> A, std::vector<int> B) {
    n=N;
    for(int i=0;i<n-1;i++){
        adj[A[i]].push_back(B[i]);
        adj[B[i]].push_back(A[i]);
    }
    pre(1);
}

int cat(int v) {
    val[v]=1;
    pair<int,int>res=cal(1);
    return min(res.first,res.second);
}

int dog(int v) {
    val[v]=2;
    pair<int,int>res=cal(1);
    return min(res.first,res.second);
}

int neighbor(int v) {
    val[v]=0;
    pair<int,int>res=cal(1);
    return min(res.first,res.second);
}

• Subtask 1: 8 / 8
• Subtask 2: 30 / 30
• Subtask 3: 0 / 62