Submission #23150

#	Time	Username	Problem	Language	Result	Execution time	Memory
23150		themastermind	Beads and wires (APIO14_beads)	C++14	13 / 100	7 ms	5120 KiB

beads

#include <bits/stdc++.h>
#define forinc(i,a,b) for(int i = a, _key = b; i <= _key; ++i)
#define fordec(i,a,b) for(int i = a, _key = b; i >= _key; --i)
#define fori(i,n) for(int i = 0, _key = n; i < _key; ++i)
#define ford(i,n) for(int i = n - 1; i >= 0; --i)
#define forvct(i,v) for(int i = 0, _key = v.size(); i < _key; ++i)
#define sqr(x) ((ll)x) * (x)
#define task "beads"
#define st first
#define nd second
#define m_p make_pair
#define m_t make_tuple
#define p_b push_back
#define p_f push_front
#define pp_b pop_back
#define pp_f pop_front
#define sn string::npos
#define heap priority_queue
#define ll long long
#define db double
#define str string
#define nn 200010

using namespace std;

const ll oo = 100000000000000007LL;

int n;
ll f[nn][4];
vector<pair<int,int> > adj[nn];

void enter()
{
    cin >> n;
    forinc(i,2,n)
    {
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].p_b(m_p(v,w));
        adj[v].p_b(m_p(u,w));
    }
}

void visit(const int &u, const int &x)
{
    f[u][0] = 0;
    f[u][1] = 0;
    f[u][2] = -oo;
    f[u][3] = -oo;
    forvct(j,adj[u])
    {
        int v = adj[u][j].st, w = adj[u][j].nd;
        if (v == x) continue;
        visit(v,u);
        ll tmp = max(max(f[v][0],f[v][1]),f[v][2] + w),
            t0 = f[u][0] + tmp,
            t1 = max(max(max(f[u][1] + tmp,f[u][0] + f[v][3] + w),f[u][2] + max(f[v][0],f[v][1]) + w),f[u][3] + f[v][0] + w),
            t2 = max(f[u][2] + tmp,f[u][0] + f[v][0] + w),
            t3 = max(f[u][3] + tmp,f[u][0] + f[v][1] + w);
        f[u][0] = t0;
        f[u][1] = t1;
        f[u][2] = t2;
        f[u][3] = t3;
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    //srand(time(NULL));
    //freopen(task".inp","r",stdin);
    //freopen(task".out","w",stdout);
    enter();
    visit(1,0);
    cout << max(f[1][0],f[1][1]);
}

• Subtask 1: 13 / 13
• Subtask 2: 0 / 15
• Subtask 3: 0 / 29
• Subtask 4: 0 / 43