oj.uz

Submission #158439

# Submission time Handle Problem Language Result Execution time Memory
158439 2019-10-17T04:51:38 Z arnold518 Beads and wires (APIO14_beads) C++14
0 / 100
 6 ms 4988 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 2e5;

int N;
vector<pii> adj[MAXN+10];
ll dp1[MAXN+10], dp2[MAXN+10];

void dfs(int now, int bef, int par)
{
    vector<ll> V;
    ll S=0;
    for(pii nxt : adj[now])
    {
        if(nxt.first==bef) continue;
        dfs(nxt.first, now, nxt.second);
        S+=max(dp1[nxt.first], dp2[nxt.first]);
        V.push_back(dp2[nxt.first]+nxt.second-max(dp1[nxt.first], dp2[nxt.first]));
    }
    sort(V.begin(), V.end(), greater<ll>());
    dp2[now]=S;
    if(V.size()>1 && V[0]+V[1]>=0) dp2[now]+=V[0]+V[1];

    dp1[now]=S;
    if(V.size()>0 && V[0]+par>=0) dp1[now]+=par+V[0];

    //printf("%d %lld %lld\n", now, dp1[now], dp2[now]);
}

int main()
{
    int i, j;

    scanf("%d", &N);
    for(i=1; i<N; i++)
    {
        int u, v, w;
        scanf("%d%d%d", &u, &v, &w);
        adj[u].push_back({v, w});
        adj[v].push_back({u, w});
    }

    dfs(1, 1, 0);
    printf("%lld", dp2[1]);
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:37:12: warning: unused variable 'j' [-Wunused-variable]
     int i, j;
            ^
beads.cpp:39:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &N);
     ~~~~~^~~~~~~~~~
beads.cpp:43:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d", &u, &v, &w);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4988 KB Output is correct
3 Correct 6 ms 4984 KB Output is correct
4 Correct 6 ms 4984 KB Output is correct
5 Correct 6 ms 4984 KB Output is correct
6 Incorrect 6 ms 4984 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #2
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4988 KB Output is correct
3 Correct 6 ms 4984 KB Output is correct
4 Correct 6 ms 4984 KB Output is correct
5 Correct 6 ms 4984 KB Output is correct
6 Incorrect 6 ms 4984 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4988 KB Output is correct
3 Correct 6 ms 4984 KB Output is correct
4 Correct 6 ms 4984 KB Output is correct
5 Correct 6 ms 4984 KB Output is correct
6 Incorrect 6 ms 4984 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4988 KB Output is correct
3 Correct 6 ms 4984 KB Output is correct
4 Correct 6 ms 4984 KB Output is correct
5 Correct 6 ms 4984 KB Output is correct
6 Incorrect 6 ms 4984 KB Output isn't correct
7 Halted 0 ms 0 KB -