Submission #1059801

#	Time	Username	Problem	Language	Result	Execution time	Memory
1059801		mispertion	Swapping Cities (APIO20_swap)	C++17	50 / 100	2063 ms	54468 KiB

swap

#include "swap.h"
#include <bits/stdc++.h>
#include <vector>

using namespace std;

const int N = 1e5 + 5;
const int infi = INT_MAX;

typedef pair<int, int> pii;

#define mp make_pair
#define pb push_back
#define F first
#define S second

struct dsu{
    int pw[N];
    vector<pii> p[N], cnt1[N], cnt2[N], sz[N];

    dsu(int n){
        for(int i = 1; i <= n; i++){
            p[i] = {{-1, i}};
            sz[i] = {{-1, 1}};
            cnt1[i] = {{-1, 0}};
            cnt2[i] = {{-1, 0}};
            pw[i] = 0;
        }
    }
    dsu(){

    }

    int getp(int v, int t){
        int pr = (--upper_bound(p[v].begin(), p[v].end(),mp(t, infi)))->S;
        if(pr == v)
            return v;
        return getp(pr, t);
    }

    int getpch(int v, int t){
        int pr = p[v].back().S;
        if(pr == v)
            return v;
        p[v].pb({t, getpch(pr, t)});
        return p[v].back().S;
    }

    void upd(int v, int nw, int t){
        if(nw == 1)
            cnt1[v].pb({t, cnt1[v].back().S - 1});
        if(nw == 2)
            cnt2[v].pb({t, cnt2[v].back().S - 1});
        if(nw == 0)
            cnt1[v].pb({t, cnt1[v].back().S + 1});
        if(nw == 1)
            cnt2[v].pb({t, cnt2[v].back().S + 1});
    }

    void uni(int a, int b, int t){
        int n1 = pw[a];
        int n2 = pw[b];
        //cout << n1 << ' ' << n2 << '\n';
        pw[a]++;
        pw[b]++;
        a = getpch(a, t);
        b = getpch(b, t);
        if(a == b){
            upd(a, n1, t);
            upd(a, n2, t);
            return;
        }
        if(sz[a] > sz[b])
            swap(a, b);
        p[a].pb({t, b});
        sz[b].pb({t, sz[a].back().S + sz[b].back().S});
        cnt1[b].pb({t, cnt1[a].back().S + cnt1[b].back().S});
        cnt2[b].pb({t, cnt2[a].back().S + cnt2[b].back().S});
        upd(b, n1, t);
        upd(b, n2, t);
    }
};

int n, m;
vector<pair<int, pair<int, int>>> edges;
dsu ds;

void init(int N, int M, std::vector<int> U, std::vector<int> V, std::vector<int> W) {
    n = N;
    m = M;
    for(int i = 0; i < m; i++){
        U[i]++;
        V[i]++;
        edges.pb({W[i], {V[i], U[i]}});
    }
    sort(edges.begin(), edges.end());
    ds = dsu(n);
    for(int i = 0; i < m; i++){
        ds.uni(edges[i].S.F, edges[i].S.S, i);
        /*cout << "comp: ";
        for(int j = 1; j <= n; j++){
            cout << ds.getp(j, infi) << ' ';
        }
        cout << '\n';
        cout << "cnt1: ";
        for(int i = 1; i <= n; i++){
            cout << ds.cnt1[ds.getp(i, infi)].back().S << ' ';
        }
        cout << '\n';
        cout << "cnt2: ";
        for(int i = 1; i <= n; i++){
            cout << ds.cnt2[ds.getp(i, infi)].back().S << ' ';
        }
        cout << '\n';*/
    }
}

int getMinimumFuelCapacity(int X, int Y) {
    X++;
    Y++;
    int lo = -1, hi = m;
    while(lo + 1 < hi){
        int m = (lo + hi) / 2;
        int x = ds.getp(X, m), y = ds.getp(Y, m);
        if(x != y){
            lo = m;
            continue;
        }
        int c1 = (--upper_bound(ds.cnt1[x].begin(), ds.cnt1[x].end(),mp(m, infi)))->S;
        int c2 = (--upper_bound(ds.cnt2[x].begin(), ds.cnt2[x].end(),mp(m, infi)))->S;
        int sz = (--upper_bound(ds.sz[x].begin(), ds.sz[x].end(),mp(m, infi)))->S;
        if(c1 == 2 && c2 == sz - 2){
            lo = m;
            continue;
        }
        hi = m;
    }
    if(hi == m)
        return -1;
    return edges[hi].F;
}

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 17 / 17
• Subtask 4: 20 / 20
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27