Submission #1037356

#	Time	Username	Problem	Language	Result	Execution time	Memory
1037356		onbert	Friend (IOI14_friend)	C++17	58 / 100	29 ms	12036 KiB

friend

#include "friend.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 5;
int n, a[maxn];
vector<int> adj[maxn][3];

int dp[maxn][2];
void dfs(int u) {
    for (int i=0;i<=2;i++) for (int v:adj[u][i]) dfs(v);
    int pt1 = 0, pt2 = 0, cur = 0;
    for (int v:adj[u][0]) cur += dp[v][1];
    for (int v:adj[u][1]) cur += dp[v][0];
    for (int v:adj[u][2]) cur += dp[v][0];
    int val = cur, mx = 0;
    for (int v:adj[u][0]) {
        while (pt1<adj[u][1].size() && adj[u][1][pt1] < v) cur += dp[adj[u][1][pt1]][1] - dp[adj[u][1][pt1]][0], pt1++;
        while (pt2<adj[u][2].size() && adj[u][2][pt2] < v) mx = max(dp[adj[u][2][pt2]][1] - dp[adj[u][2][pt2]][0], mx), pt2++;
        val = max(cur + mx, val);
        cur += dp[v][0] - dp[v][1];
    }
    while (pt1<adj[u][1].size()) cur += dp[adj[u][1][pt1]][1] - dp[adj[u][1][pt1]][0], pt1++;
    while (pt2<adj[u][2].size()) mx = max(dp[adj[u][2][pt2]][1] - dp[adj[u][2][pt2]][0], mx), pt2++;
    val = max(cur + mx, val);

    dp[u][0] = 0;
    for (int v:adj[u][0]) dp[u][0] += dp[v][1];
    for (int v:adj[u][1]) dp[u][0] += dp[v][0];
    for (int v:adj[u][2]) dp[u][0] += dp[v][0];
    
    dp[u][1] = a[u];
    for (int v:adj[u][0]) dp[u][1] += dp[v][0];
    for (int v:adj[u][1]) dp[u][1] += dp[v][1];
    for (int v:adj[u][2]) dp[u][1] += dp[v][0];
    dp[u][1] = max({val, dp[u][0], dp[u][1]});
}

int findSample(int N, int confidence[], int host[], int t[]){
	n = N;
    for (int i=0;i<n;i++) a[i] = confidence[i];
    for (int i=1;i<n;i++) adj[host[i]][t[i]].push_back(i);
    dfs(0);
    // for (int j=0;j<=1;j++) {
    //     cout << j << endl;
    //     for (int i=0;i<n;i++) cout << dp[i][j] << " "; cout << endl;
    // }
    return dp[0][1];
}

Compilation message (stderr)

friend.cpp: In function 'void dfs(int)':
friend.cpp:17:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |         while (pt1<adj[u][1].size() && adj[u][1][pt1] < v) cur += dp[adj[u][1][pt1]][1] - dp[adj[u][1][pt1]][0], pt1++;
      |                ~~~^~~~~~~~~~~~~~~~~
friend.cpp:18:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |         while (pt2<adj[u][2].size() && adj[u][2][pt2] < v) mx = max(dp[adj[u][2][pt2]][1] - dp[adj[u][2][pt2]][0], mx), pt2++;
      |                ~~~^~~~~~~~~~~~~~~~~
friend.cpp:22:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     while (pt1<adj[u][1].size()) cur += dp[adj[u][1][pt1]][1] - dp[adj[u][1][pt1]][0], pt1++;
      |            ~~~^~~~~~~~~~~~~~~~~
friend.cpp:23:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     while (pt2<adj[u][2].size()) mx = max(dp[adj[u][2][pt2]][1] - dp[adj[u][2][pt2]][0], mx), pt2++;
      |            ~~~^~~~~~~~~~~~~~~~~

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