Submission #675186

#	Time	Username	Problem	Language	Result	Execution time	Memory
675186		abcvuitunggio	Uzastopni (COCI15_uzastopni)	C++17	80 / 160	1 ms	1236 KiB

uzastopni

#include <iostream>
#include <bitset>
#include <vector>
#include <algorithm>
using namespace std;
bool dp[10001][101][101];
int n,a[101],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]][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][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][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++)
        sort(ke[i].begin(),ke[i].end(),[](int i, int j){
                return a[i]<a[j];
             });
    dfs(1);
    int cnt=0,cnt2=0;
    for (int i=1;i<=100;i++)
        cnt+=dp[1][i][a[1]],cnt2+=dp[1][a[1]][i];
    cout << cnt*cnt2;
}

Compilation message (stderr)

uzastopni.cpp: In function 'void dfs(int)':
uzastopni.cpp:14:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for (int i=0;i<ke[u].size();i++){
      |                  ~^~~~~~~~~~~~~
uzastopni.cpp:22:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     for (int it=pos2;it<ke[u].size();it++){
      |                      ~~^~~~~~~~~~~~~

• Subtask 1: 80 / 160