답안 #31602

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
31602 2017-08-30T02:49:51 Z minkank 구슬과 끈 (APIO14_beads) C++14
28 / 100
1000 ms 2364 KB
#include <bits/stdc++.h>
using namespace std;

typedef pair<int, int> ii;

const int N = 1e4 + 5;

int n, dp[N][2], ans;
vector<ii> a[N], b[N];
vector<int> l[N], r[N];

void dfs(int u, int p) {
    b[u].clear();
    b[u].push_back(ii(0, 0));
    for(int i = 0; i < a[u].size(); ++i) {
        int v = a[u][i].first;
        if(v == p) continue;
        dfs(v, u);
        b[u].push_back(a[u][i]);
    }
    l[u].assign(b[u].size() + 1, 0); r[u].assign(b[u].size() + 1, 0);
    for(int i = 1; i < b[u].size(); ++i) {
        int v = b[u][i].first, w = b[u][i].second;
        l[u][i] = l[u][i - 1] + max(dp[v][1] + w, dp[v][0]);
    }
    for(int i = b[u].size() - 1; i >= 1; --i) {
        int v = b[u][i].first, w = b[u][i].second;
        r[u][i] = r[u][i + 1] + max(dp[v][1] + w, dp[v][0]);
    }
    dp[u][0] = l[u][b[u].size() - 1];
    for(int i = 1; i < b[u].size(); ++i) {
        int v = b[u][i].first, w = b[u][i].second;
        dp[u][1] = max(dp[u][1], l[u][i - 1] + r[u][i + 1] + dp[v][0] + w);
    }
    if(b[u].size() == 1) dp[u][1] = -1e9;
}

int main() {
    cin >> n;
    for(int i = 1; i < n; ++i) {
        int u, v, w;
        cin >> u >> v >> w;
        a[u].push_back(ii(v, w));
        a[v].push_back(ii(u, w));
    }
    for(int i = 1; i <= n; ++i) {
        memset(dp, 0, sizeof dp);
        dfs(i, i);
        ans = max(ans, dp[i][0]);
    }
    cout << ans;
}

Compilation message

beads.cpp: In function 'void dfs(int, int)':
beads.cpp:15:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < a[u].size(); ++i) {
                    ~~^~~~~~~~~~~~~
beads.cpp:22:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1; i < b[u].size(); ++i) {
                    ~~^~~~~~~~~~~~~
beads.cpp:31:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1; i < b[u].size(); ++i) {
                    ~~^~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 1408 KB Output is correct
2 Correct 3 ms 1408 KB Output is correct
3 Correct 3 ms 1408 KB Output is correct
4 Correct 3 ms 1408 KB Output is correct
5 Correct 3 ms 1408 KB Output is correct
6 Correct 3 ms 1408 KB Output is correct
7 Correct 2 ms 1280 KB Output is correct
8 Correct 3 ms 1408 KB Output is correct
9 Correct 3 ms 1280 KB Output is correct
10 Correct 3 ms 1408 KB Output is correct
11 Correct 3 ms 1408 KB Output is correct
12 Correct 3 ms 1408 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 1408 KB Output is correct
2 Correct 3 ms 1408 KB Output is correct
3 Correct 3 ms 1408 KB Output is correct
4 Correct 3 ms 1408 KB Output is correct
5 Correct 3 ms 1408 KB Output is correct
6 Correct 3 ms 1408 KB Output is correct
7 Correct 2 ms 1280 KB Output is correct
8 Correct 3 ms 1408 KB Output is correct
9 Correct 3 ms 1280 KB Output is correct
10 Correct 3 ms 1408 KB Output is correct
11 Correct 3 ms 1408 KB Output is correct
12 Correct 3 ms 1408 KB Output is correct
13 Correct 3 ms 1408 KB Output is correct
14 Correct 4 ms 1408 KB Output is correct
15 Correct 3 ms 1408 KB Output is correct
16 Correct 5 ms 1408 KB Output is correct
17 Correct 5 ms 1408 KB Output is correct
18 Correct 5 ms 1408 KB Output is correct
19 Correct 5 ms 1408 KB Output is correct
20 Correct 5 ms 1408 KB Output is correct
21 Correct 5 ms 1408 KB Output is correct
22 Correct 5 ms 1408 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 1408 KB Output is correct
2 Correct 3 ms 1408 KB Output is correct
3 Correct 3 ms 1408 KB Output is correct
4 Correct 3 ms 1408 KB Output is correct
5 Correct 3 ms 1408 KB Output is correct
6 Correct 3 ms 1408 KB Output is correct
7 Correct 2 ms 1280 KB Output is correct
8 Correct 3 ms 1408 KB Output is correct
9 Correct 3 ms 1280 KB Output is correct
10 Correct 3 ms 1408 KB Output is correct
11 Correct 3 ms 1408 KB Output is correct
12 Correct 3 ms 1408 KB Output is correct
13 Correct 3 ms 1408 KB Output is correct
14 Correct 4 ms 1408 KB Output is correct
15 Correct 3 ms 1408 KB Output is correct
16 Correct 5 ms 1408 KB Output is correct
17 Correct 5 ms 1408 KB Output is correct
18 Correct 5 ms 1408 KB Output is correct
19 Correct 5 ms 1408 KB Output is correct
20 Correct 5 ms 1408 KB Output is correct
21 Correct 5 ms 1408 KB Output is correct
22 Correct 5 ms 1408 KB Output is correct
23 Execution timed out 1074 ms 2364 KB Time limit exceeded
24 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 1408 KB Output is correct
2 Correct 3 ms 1408 KB Output is correct
3 Correct 3 ms 1408 KB Output is correct
4 Correct 3 ms 1408 KB Output is correct
5 Correct 3 ms 1408 KB Output is correct
6 Correct 3 ms 1408 KB Output is correct
7 Correct 2 ms 1280 KB Output is correct
8 Correct 3 ms 1408 KB Output is correct
9 Correct 3 ms 1280 KB Output is correct
10 Correct 3 ms 1408 KB Output is correct
11 Correct 3 ms 1408 KB Output is correct
12 Correct 3 ms 1408 KB Output is correct
13 Correct 3 ms 1408 KB Output is correct
14 Correct 4 ms 1408 KB Output is correct
15 Correct 3 ms 1408 KB Output is correct
16 Correct 5 ms 1408 KB Output is correct
17 Correct 5 ms 1408 KB Output is correct
18 Correct 5 ms 1408 KB Output is correct
19 Correct 5 ms 1408 KB Output is correct
20 Correct 5 ms 1408 KB Output is correct
21 Correct 5 ms 1408 KB Output is correct
22 Correct 5 ms 1408 KB Output is correct
23 Execution timed out 1074 ms 2364 KB Time limit exceeded
24 Halted 0 ms 0 KB -