oj.uz

Submission #758825

# Submission time Handle Problem Language Result Execution time Memory
758825 2023-06-15T10:54:51 Z Username4132 Beads and wires (APIO14_beads) C++14
100 / 100
 159 ms 33432 KB 
#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
using pii = pair<int, int>;
#define forn(i, n) for(int i=0; i<(int)n; ++i)
#define PB push_back
#define F first
#define S second

const int MAXN=200010, INF=2000000010;
int n, dp[4][MAXN];
vector<pii> g[MAXN];

void dfs(int v, int p, int cost){
    int sz = g[v].size() - (v!=0), cnt=0;
    vector<pii> d1(sz), d2(sz), d3(sz);
    for(pii to:g[v]) if(to.F!=p){
        dfs(to.F, v, to.S);
        dp[1][v]+=dp[0][to.F];
        d1[cnt]={to.S+dp[1][to.F]-dp[0][to.F], cnt};
        d2[cnt]={to.S+dp[2][to.F]-dp[0][to.F], cnt};
        d3[cnt]={dp[3][to.F]-dp[0][to.F], cnt};
        cnt++;
    }
    sort(d1.begin(), d1.end(), greater<pii>());
    sort(d2.begin(), d2.end(), greater<pii>());
    sort(d3.begin(), d3.end(), greater<pii>());

    dp[0][v]=(sz==0? 0 : max(d1[0].F + cost, 0))+dp[1][v];
    dp[2][v]=dp[1][v];
    if(sz>1){
        int mx;
        if(d1[0].S!=d2[0].S) mx=d1[0].F+d2[0].F;
        else mx=max(d1[0].F+d2[1].F, d1[1].F+d2[0].F);
        if(mx>0) dp[2][v]=mx+dp[1][v];
    }
    if(sz>0) dp[2][v]=max(dp[2][v], dp[1][v]+d3[0].F);
    if(sz>0) dp[3][v]=max(dp[3][v], dp[1][v]+d2[0].F+cost);
    dp[3][v]=max(dp[3][v], dp[2][v]);
    dp[3][v]=max(dp[3][v], dp[0][v]);
}

int main(){
    scanf("%d", &n);
    forn(i, n-1){
        int a, b, c;
        scanf("%d %d %d", &a, &b, &c); --a, --b;
        g[a].PB({b, c}), g[b].PB({a, c});
    }
    dfs(0, 0, -INF);
    printf("%d\n", dp[3][0]);
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:45:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
beads.cpp:48:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         scanf("%d %d %d", &a, &b, &c); --a, --b;
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5004 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 3 ms 5008 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 2 ms 4948 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5004 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 3 ms 5008 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 2 ms 4948 KB Output is correct
13 Correct 3 ms 5012 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 4 ms 4948 KB Output is correct
18 Correct 1 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 4 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5004 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 3 ms 5008 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 2 ms 4948 KB Output is correct
13 Correct 3 ms 5012 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 4 ms 4948 KB Output is correct
18 Correct 1 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 4 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct
23 Correct 5 ms 5248 KB Output is correct
24 Correct 4 ms 5332 KB Output is correct
25 Correct 4 ms 5244 KB Output is correct
26 Correct 7 ms 5624 KB Output is correct
27 Correct 8 ms 5656 KB Output is correct
28 Correct 7 ms 5920 KB Output is correct
29 Correct 7 ms 5844 KB Output is correct
30 Correct 7 ms 5844 KB Output is correct
31 Correct 7 ms 6868 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5004 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 3 ms 5008 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 2 ms 4948 KB Output is correct
13 Correct 3 ms 5012 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 4 ms 4948 KB Output is correct
18 Correct 1 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 4 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct
23 Correct 5 ms 5248 KB Output is correct
24 Correct 4 ms 5332 KB Output is correct
25 Correct 4 ms 5244 KB Output is correct
26 Correct 7 ms 5624 KB Output is correct
27 Correct 8 ms 5656 KB Output is correct
28 Correct 7 ms 5920 KB Output is correct
29 Correct 7 ms 5844 KB Output is correct
30 Correct 7 ms 5844 KB Output is correct
31 Correct 7 ms 6868 KB Output is correct
32 Correct 42 ms 8528 KB Output is correct
33 Correct 23 ms 8356 KB Output is correct
34 Correct 22 ms 8428 KB Output is correct
35 Correct 113 ms 19020 KB Output is correct
36 Correct 111 ms 19056 KB Output is correct
37 Correct 154 ms 19116 KB Output is correct
38 Correct 137 ms 23760 KB Output is correct
39 Correct 115 ms 23428 KB Output is correct
40 Correct 123 ms 23580 KB Output is correct
41 Correct 159 ms 33432 KB Output is correct