Submission #423443

#	Time	Username	Problem	Language	Result	Execution time	Memory
423443		Theo830	Friend (IOI14_friend)	C++17	0 / 100	6 ms	2124 KiB

friend

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll INF = 1e9;
ll MOD = 998244353;
typedef pair<ll,ll> ii;
#define iii pair<int,int>
#define f(i,a,b) for(ll i = a;i < b;i++)
#define pb push_back
#define vll vector<ll>
#define F first
#define S second
#define all(x) (x).begin(), (x).end()
///I hope I will get uprating and don't make mistakes
///I will never stop programming
///sqrt(-1) Love C++
///Please don't hack me
///@TheofanisOrfanou Theo830
///Think different approaches (bs,dp,greedy,graphs,shortest paths,mst)
///Stay Calm
///Look for special cases
///Beware of overflow and array bounds
///Think the problem backwards
///Training
vector<vll>adj;
ll arr[1005];
ll dp[1005][2];
ll solve(ll idx,bool ep){
    if(dp[idx][ep] != -1){
        return dp[idx][ep];
    }
    ll sum = 0;
    ll maxi = 0;
    for(auto x:adj[idx]){
        if(x > idx){
            sum += solve(x,0);
            maxi = max(maxi,arr[x] + solve(x,1) - solve(x,0));
        }
    }
    if(!ep){
        sum += maxi;
    }
    return dp[idx][ep] = sum;
}
int findSample(int n, int confidence[], int host[], int protocol[]){
    adj.assign(n+5,vll());
    f(i,0,n){
        arr[i] = confidence[i];
    }
    f(i,1,n){
        ll v = host[i];
        if(protocol[i] == 0){
            adj[v].pb(i);
            adj[i].pb(v);
        }
        else if(protocol[i] == 1){
            for(auto x:adj[v]){
                adj[i].pb(x);
                adj[x].pb(i);
            }
        }
        else{
            for(auto x:adj[v]){
                adj[i].pb(x);
                adj[x].pb(i);
            }
            adj[v].pb(i);
            adj[i].pb(v);
        }
    }
    memset(dp,-1,sizeof dp);
    return max(solve(0,0),arr[0] + solve(0,1));
}

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