Submission #675197

#	Time	Username	Problem	Language	Result	Execution time	Memory
675197		vjudge1	Uzastopni (COCI15_uzastopni)	C++17	160 / 160	99 ms	17864 KiB

uzastopni

#include <iostream>
#include <bitset>
#include <vector>
#include <algorithm>
#include <cstdio>
using namespace std;
bitset <101> dp[10001][101];
int n,a[10001],u,v,res;
vector <int> ke[10001];
void dfs(int u){
    dp[u][a[u]][a[u]]=1;
    if (ke[u].empty())
        return;
    int pos=-1,pos2=1e9;
    for (int i=0;i<ke[u].size();i++){
        int v=ke[u][i];
        dfs(v);
        if (a[v]<=a[u])
            pos=max(pos,i);
        if (a[v]>=a[u])
            pos2=min(pos2,i);
    }
    for (int it=pos2;it<ke[u].size();it++){
        int v=ke[u][it];
        for (int j=a[u];j<=100;j++)
            if (!dp[u][a[u]][j])
                for (int i=a[u]+1;i<=j;i++)
                    dp[u][a[u]][j]=dp[u][a[u]][j]|(dp[u][a[u]][i-1]&dp[v][i][j]);
    }
    for (int it=pos;it>=0;it--){
        int v=ke[u][it];
        for (int j=1;j<=a[u];j++)
            if (!dp[u][j][a[u]])
                for (int i=j;i<a[u];i++)
                    dp[u][j][a[u]]=dp[u][j][a[u]]|(dp[u][i+1][a[u]]&dp[v][j][i]);
    }
    for (int i=1;i<=a[u];i++)
        for (int j=a[u];j<=100;j++)
            dp[u][i][j]=dp[u][i][j]|(dp[u][i][a[u]]&dp[u][a[u]][j]);
}
int main(){
    ios_base::sync_with_stdio(NULL);cin.tie(nullptr);
    cin >> n;
    for (int i=1;i<=n;i++)
        cin >> a[i];
    for (int i=1;i<n;i++){
        cin >> u >> v;
        ke[u].push_back(v);
    }
    for (int i=1;i<=n;i++)
        if (!ke[i].empty())
            sort(ke[i].begin(),ke[i].end(),[](int i, int j){
                    return a[i]<a[j];
                 });
    dfs(1);
    int cnt=0;
    for (int i=1;i<=100;i++)
        for (int j=1;j<=100;j++)
            cnt+=dp[1][i][j];
    cout << cnt;
}

Compilation message (stderr)

uzastopni.cpp: In function 'void dfs(int)':
uzastopni.cpp:15:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |     for (int i=0;i<ke[u].size();i++){
      |                  ~^~~~~~~~~~~~~
uzastopni.cpp:23:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     for (int it=pos2;it<ke[u].size();it++){
      |                      ~~^~~~~~~~~~~~~

• Subtask 1: 160 / 160