Submission #882387

#	Time	Username	Problem	Language	Result	Execution time	Memory
882387		12345678	Putovanje (COCI20_putovanje)	C++17	110 / 110	110 ms	38744 KiB

putovanje

#include <bits/stdc++.h>

using namespace std;

const int nx=2e5+5, kx=18;
long long n, u, v, c[nx], c2[nx], dp[nx], cnt[nx], res, pa[nx][kx], lvl[nx];
vector<pair<int, int>> d[nx];

void dfs(int u, int p)
{
    lvl[u]=lvl[p]+1; pa[u][0]=p;
    for (int i=1; i<kx; i++) pa[u][i]=pa[pa[u][i-1]][i-1];
    for (auto [v, idx]:d[u]) if (v!=p) dfs(v, u);
}

int lca(int u, int v)
{
    if (lvl[u]>lvl[v]) swap(u, v);
    for (int i=kx-1; i>=0; i--) if (lvl[pa[v][i]]>=lvl[u]) v=pa[v][i];
    if (u==v) return v;
    for (int i=kx-1; i>=0; i--) if (pa[u][i]!=pa[v][i]) u=pa[u][i], v=pa[v][i];
    return pa[u][0];
}

void dfs2(int u, int p, int idx)
{
    for (auto [v, id]:d[u]) if (v!=p) dfs2(v, u, id), dp[u]+=dp[v];
    cnt[idx]=dp[u];
}

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    for (int i=1; i<n; i++) cin>>u>>v>>c[i]>>c2[i], d[u].push_back({v, i}), d[v].push_back({u, i});
    dfs(1, 1);
    for (int i=2; i<=n; i++) dp[i]++, dp[i-1]++, dp[lca(i, i-1)]-=2;
    dfs2(1, 1, 0);
    for (int i=1; i<n; i++) res+=min(c[i]*cnt[i], c2[i]);
    cout<<res;
}

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 65 / 65