Submission #798479

#	Time	Username	Problem	Language	Result	Execution time	Memory
798479		Khizri	Friend (IOI14_friend)	C++17	46 / 100	109 ms	65536 KiB

friend

#include "friend.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define F first
#define S second
#define INF 1e18
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pii pair<int,int>
#define pll pair<ll,ll>
#define OK cout<<"Ok"<<endl;
#define MOD (ll)(1e9+7)
const int mxn=1005;
int n,arr[mxn],rel[mxn][mxn],ans=0,dp[mxn][2],color[mxn],mt[mxn],used[mxn];
vector<int>vt[mxn];
vector<int>vt2[mxn];
vector<int>odd,even;
void dfs(int u,int p){
    for(int v:vt[u]){
        if(v!=p){
            dfs(v,u);
            dp[u][0]+=dp[v][1];
            dp[u][1]+=max(dp[v][0],dp[v][1]);
        }
    }
    dp[u][0]+=arr[u];
    ans=max(ans,dp[u][0]);
    ans=max(ans,dp[u][1]);
}
void dfs2(int u,int dep){
    if(dep%2==0){
        even.pb(u);
    }
    else{
        odd.pb(u);
    }
    color[u]=1;
    for(int v:vt[u]){
        if(color[v]) continue;
        dfs2(v,dep+1);
    }
}
bool kuhn(int u){
    if(used[u]) return false;
    used[u]=1;
    for(int v:vt2[u]){
        if(mt[v]==-1||kuhn(mt[v])){
            mt[v]=u;
            return true;
        }
    }
    return false;
}
int solve(){
    dfs2(1,0);
    int x=even.size();
    int y=odd.size();
    int num=0;
    for(int u:even){
        num++;
        for(int j=0;j<odd.size();j++){
            int v=odd[j];
            if(rel[u][v]){
                vt2[num].pb(j+1);
            }
        }
    }
    for(int i=1;i<=y;i++){
        mt[i]=-1;
    }
    for(int i=1;i<=x;i++){
        memset(used,0,sizeof(used));
        kuhn(i);
    }
    ans=0;
    for(int i=1;i<=y;i++){
        if(mt[i]!=-1) ans++;
    }
    return n-ans;
}
int findSample(int N,int confidence[],int host[],int protocol[]){
	n=N;
    for(int i=0;i<n;i++){
        arr[i+1]=confidence[i];
    }
    bool task2=true,task3=true,task4=true,task5=true;
    for(int i=1;i<n;i++){
        int type=protocol[i];
        if(type!=1) task2=false;
        if(type!=2) task3=false;
        if(type!=0) task4=false;
        if(type==2) task5=false;
    }
    for(int i=1;i<=n;i++){
        if(arr[i]>1) task5=false;
    }
    if(task2){
        int mx=0;
        for(int i=1;i<=n;i++){
            mx+=arr[i];
        }
        return mx;
    }
    if(task3){
        int mx=0;
        for(int i=1;i<=n;i++){
            mx=max(mx,arr[i]);
        }
        return mx;
    }
    for(int i=1;i<n;i++){
        int node=host[i]+1;
        int type=protocol[i];
        if(type==0){
            vt[node].pb(i+1);
            vt[i+1].pb(node);
        }
        else if(type==1){
            int sz=vt[node].size();
            for(int j=0;j<sz;j++){
                int v=vt[node][j];
                vt[v].pb(i+1);
                vt[i+1].pb(v);
            }
        }
        else{
            int sz=vt[node].size();
            for(int j=0;j<sz;j++){
                int v=vt[node][j];
                vt[v].pb(i+1);
                vt[i+1].pb(v);
            }
            vt[node].pb(i+1);
            vt[i+1].pb(node);
        }
    }
    for(int i=1;i<=n;i++){
        for(int v:vt[i]){
            rel[i][v]=1;
        }
    }
    if(task5){
        return solve();
    }
    if(task4){
        dfs(1,-1);
        return ans;
    }
    ans=0;
    for(int mask=1;mask<(1<<n);mask++){
        vector<int>v;
        int sum=0;
        for(int i=0;i<n;i++){
            if(mask&(1<<i)){
                v.pb(i+1);
                sum+=arr[i+1];
            }
        }
        bool ok=true;
        for(int i=0;i<v.size();i++){
            for(int j=i+1;j<v.size();j++){
                if(rel[v[i]][v[j]]){
                    ok=false;
                }
            }
        }
        if(ok) ans=max(ans,sum);
    }
    return ans;
}
/*
g++ friend.cpp grader.cpp ; .\a.exe
6
13 3 6 20 10 15
0 0
0 1
1 2
2 1
0 0
6
1 1 1 1 1 1
0 0
0 0 
1 0
1 0
1 1 
*/

Compilation message (stderr)

friend.cpp: In function 'int solve()':
friend.cpp:63:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |         for(int j=0;j<odd.size();j++){
      |                     ~^~~~~~~~~~~
friend.cpp: In function 'int findSample(int, int*, int*, int*)':
friend.cpp:162:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  162 |         for(int i=0;i<v.size();i++){
      |                     ~^~~~~~~~~
friend.cpp:163:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  163 |             for(int j=i+1;j<v.size();j++){
      |                           ~^~~~~~~~~

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