Submission #238370

#	Time	Username	Problem	Language	Result	Execution time	Memory
238370		oscarsierra12	Friend (IOI14_friend)	C++14	27 / 100	1092 ms	6016 KiB

friend

#include "friend.h"
#include <bits/stdc++.h>

#define pb    push_back

using namespace std ;

// Find out best sample

const int N = 100010 ;

int confi[N] ;
int dp [N][2];
vector <int> G[N][2] ;

int go ( int u, int flag ) {
    auto &rf = dp[u][flag];
    if ( rf!=-1 ) return rf ;
    if ( flag ) {
        ///take
        int x = confi[u] ;
        for ( auto v:G[u][0] ) x += go( v, 0 ) ;
        for ( auto v:G[u][1] ) x += go( v, 1 ) ;
        rf = x ;
        ///dont take
        x = 0 ;
        int it1 = 0, it2 = 0, rep = 0, rep2 =0 ;
        for ( auto v:G[u][0] ) rep += go(v, 1) ;
        for ( auto v:G[u][1] ) rep2 += go(v, 0) ;
        while ( it1 < G[u][0].size() ) {
            while ( it2 < G[u][1].size() && G[u][1][it2] < G[u][0][it1] ) {
                rep2 -= go(G[u][1][it2], 0) ;
                rep2 += go(G[u][1][it2], 1) ;
                rep2++ ;
            }
            x = max ( x, rep2+rep ) ;
            rep -= go(G[u][0][it1],1) ;
            rep += go(G[u][0][it1],0) ;
            it1++ ;
        }
        rf = max ( rf, x ) ;

    }
    else {
        int x = 0 ;
        for ( auto v:G[u][1] ) x += go ( v, 0 ) ;
        for ( auto v:G[u][0] ) x += go ( v, 1 ) ;
        rf = x ;
    }
    return rf ;
}

int findSample(int n,int confidence[],int host[],int protocol[]){
    for ( int i = 0 ; i < n ; ++i ) confi[i] = confidence[i] ;
    for ( int i = 1 ; i < n ; ++i ) G[host[i]][protocol[i]].push_back ( i ) ;
    memset ( dp,-1,sizeof dp ) ;
    return go(0,1) ;
}

Compilation message (stderr)

friend.cpp: In function 'int go(int, int)':
friend.cpp:30:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while ( it1 < G[u][0].size() ) {
                 ~~~~^~~~~~~~~~~~~~~~
friend.cpp:31:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while ( it2 < G[u][1].size() && G[u][1][it2] < G[u][0][it1] ) {
                     ~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 11
• Subtask 2: 8 / 8
• Subtask 3: 0 / 8
• Subtask 4: 19 / 19
• Subtask 5: 0 / 23
• Subtask 6: 0 / 31