Submission #769509

# Submission time Handle Problem Language Result Execution time Memory
769509 2023-06-29T17:04:47 Z vjudge1 Paths (RMI21_paths) C++17
36 / 100
600 ms 15708 KB
#include <bits/stdc++.h>

using namespace std;

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

#define pb push_back
#define ss second
#define ff first
#define all(x) (x).begin(), (x).end()

const int nax = 1e5 + 4;
int n, k, sz = 1;
vector<pii> adj[nax];
vector<pll> st;
vector<ll> lazy;
ll d[nax];
int dpar[nax];
int par[nax], vis[nax], eul[nax], endeul[nax], cor[nax];
int cureul = -1;
void dfs(int x, ll curd, int p)
{
    par[x] = p;
    d[x] = curd;
    dpar[x] = curd - d[p];
    vis[x] = 0;
    eul[x] = ++cureul;
    cor[cureul] = x;
    for(auto e: adj[x])
    {
        if(e.ff == p)
            continue;
        dfs(e.ff, curd + e.ss, x);
    }
    endeul[x] = cureul;
}
void build(int p, int l, int r)
{
    if(l == r)
    {
        st[p] = {d[cor[l]], cor[l]};
        return ;
    }
    build(2 * p, l, (l + r)/2);
    build(2 * p + 1, (l + r)/2  + 1, r);
    st[p] = max(st[2 * p], st[2 * p + 1]);
}
void propagate(int p, int l, int r)
{
    if(lazy[p])
    {
        if(l != r)
        {
            lazy[2 * p] += lazy[p];
            lazy[2 * p + 1] += lazy[p];
        }
        st[p].ff += lazy[p];
        lazy[p] = 0ll;
    }
}
void update(int p, int l, int r, int i, int j, ll val)
{
    propagate(p, l, r);
    if(i > j)
        return ;
    if(l >= i && r <= j)
    {
        lazy[p] += val;
        propagate(p, l, r);
        return ;
    }
    int m = (l + r)/2;
    update(2 * p, l, m, i, min(j, m), val);
    update(2 * p + 1, m + 1, r, max(i, m + 1), j, val);
    pll a ={st[2 * p].ff + lazy[2 * p], st[2 * p].ss} ;
    pll b ={st[2 * p + 1].ff + lazy[2 * p + 1], st[2 * p + 1].ss};
    st[p] = max(a,b);
    return ;
}
pll query(int p, int l, int r, int i, int j)
{
    propagate(p, l, r);
    if(i > j)
        return {0ll, 0ll};
    if(l >= i && r <= j)
        return st[p];
    int m = (l + r)/2;
    return max(query(2 * p, l, m, i, min(j, m)),
               query(2 * p + 1, m + 1, r, max(i, m + 1), j));
}
void solve()
{
    cin >> n >> k;
    for(int i=  1; i < n; i++)
    {
        int a, b;
        cin >> a >> b;
        ll c; cin >> c;
        adj[a].pb({b, c});
        adj[b].pb({a, c});
    }
    dfs(1, 0, 0);
    while(sz < n)
        sz = (sz << 1);
    lazy.assign(2 * sz + 1, 0);
    st.assign(2 * sz + 1, {0, 0});

    for(int root = 1; root <= n; root++)
    {

        if(k > 1)
        {
            cureul = -1;
            dfs(root, 0, 0);
            build(1, 0, sz - 1);
            lazy.assign(2 * sz + 1, 0);
            vis[root] = 1;
            ll ans = 0ll;
            for(int i = 1;i <= k; i++)
            {
                propagate(1, 0, sz - 1);
                pll o = st[1];
                if(o.ff == 0)
                    break;
                int cur = o.ss;
                ans += o.ff;
                while(!vis[cur])
                {
                    update(1, 0, sz - 1, eul[cur], endeul[cur], -dpar[cur]);
                    vis[cur] = 1;
                    cur=  par[cur];
                }
            }
            cout << ans << '\n';
        }
        else
        {
            update(1, 0, sz - 1, eul[root], endeul[root], -d[root]);
            update(1, 0, sz - 1, 0, eul[root] - 1, d[root]);
            update(1, 0, sz - 1, endeul[root] + 1, n - 1, d[root]);

            propagate(1, 0, sz - 1);
            pll o = st[1];

            update(1, 0, sz - 1, eul[root], endeul[root], d[root]);
            update(1, 0, sz - 1, 0, eul[root] - 1, -d[root]);
            update(1, 0, sz - 1, endeul[root] + 1, n - 1, -d[root]);
        }
    }
}

int32_t main()
{
    ios::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    int tt = 1;
    while(tt--)
        solve();
}

Compilation message

Main.cpp: In function 'void solve()':
Main.cpp:145:17: warning: variable 'o' set but not used [-Wunused-but-set-variable]
  145 |             pll o = st[1];
      |                 ^
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 6 ms 2728 KB Output is correct
4 Correct 8 ms 2724 KB Output is correct
5 Correct 4 ms 2644 KB Output is correct
6 Correct 9 ms 2724 KB Output is correct
7 Correct 7 ms 2720 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 6 ms 2728 KB Output is correct
4 Correct 8 ms 2724 KB Output is correct
5 Correct 4 ms 2644 KB Output is correct
6 Correct 9 ms 2724 KB Output is correct
7 Correct 7 ms 2720 KB Output is correct
8 Correct 120 ms 2816 KB Output is correct
9 Correct 194 ms 2852 KB Output is correct
10 Correct 208 ms 2804 KB Output is correct
11 Correct 73 ms 2820 KB Output is correct
12 Correct 122 ms 2772 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 6 ms 2728 KB Output is correct
4 Correct 8 ms 2724 KB Output is correct
5 Correct 4 ms 2644 KB Output is correct
6 Correct 9 ms 2724 KB Output is correct
7 Correct 7 ms 2720 KB Output is correct
8 Correct 120 ms 2816 KB Output is correct
9 Correct 194 ms 2852 KB Output is correct
10 Correct 208 ms 2804 KB Output is correct
11 Correct 73 ms 2820 KB Output is correct
12 Correct 122 ms 2772 KB Output is correct
13 Execution timed out 864 ms 2944 KB Time limit exceeded
14 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 213 ms 15708 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 6 ms 2728 KB Output is correct
4 Correct 8 ms 2724 KB Output is correct
5 Correct 4 ms 2644 KB Output is correct
6 Correct 9 ms 2724 KB Output is correct
7 Correct 7 ms 2720 KB Output is correct
8 Correct 120 ms 2816 KB Output is correct
9 Correct 194 ms 2852 KB Output is correct
10 Correct 208 ms 2804 KB Output is correct
11 Correct 73 ms 2820 KB Output is correct
12 Correct 122 ms 2772 KB Output is correct
13 Execution timed out 864 ms 2944 KB Time limit exceeded
14 Halted 0 ms 0 KB -