Submission #928528

#	Time	Username	Problem	Language	Result	Execution time	Memory
928528		GrindMachine	자리 배치 (IOI18_seats)	C++17	100 / 100	3017 ms	119568 KiB

seats

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi
http://www.algonotes.com/en/solutions-ioi2018/

*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

#include "seats.h"

template<typename T>
struct lazysegtree {
    /*=======================================================*/

    struct data {
        int mn,mn_cnt;
    };

    struct lazy {
        int a;
    };

    data d_neutral = {inf1,0};
    lazy l_neutral = {0};

    void merge(data &curr, data &left, data &right) {
        if(left.mn <= right.mn) curr = left;
        else curr = right;
        if(left.mn == right.mn) curr.mn_cnt += right.mn_cnt;
    }

    void create(int x, int lx, int rx, T v) {
        tr[x].mn = 0;
        tr[x].mn_cnt = 1;
    }

    void modify(int x, int lx, int rx, T v) {
        lz[x].a = v;
    }

    void propagate(int x, int lx, int rx) {
        int v = lz[x].a;
        if(!v) return;

        tr[x].mn += v;

        if(rx-lx > 1){
            lz[2*x+1].a += v;
            lz[2*x+2].a += v;
        }

        lz[x] = l_neutral;
    }

    /*=======================================================*/

    int siz = 1;
    vector<data> tr;
    vector<lazy> lz;

    lazysegtree() {

    }

    lazysegtree(int n) {
        while (siz < n) siz *= 2;
        tr.assign(2 * siz, d_neutral);
        lz.assign(2 * siz, l_neutral);
    }

    void build(int n, int x, int lx, int rx) {
        if (rx - lx == 1) {
            if (lx < n) {
                create(x, lx, rx, 0);
            }

            return;
        }

        int mid = (lx + rx) / 2;

        build(n, 2 * x + 1, lx, mid);
        build(n, 2 * x + 2, mid, rx);

        merge(tr[x], tr[2 * x + 1], tr[2 * x + 2]);
    }

    void build(int n) {
        build(n, 0, 0, siz);
    }

    void rupd(int l, int r, T v, int x, int lx, int rx) {
        propagate(x, lx, rx);

        if (lx >= r or rx <= l) return;
        if (lx >= l and rx <= r) {
            modify(x, lx, rx, v);
            propagate(x, lx, rx);
            return;
        }

        int mid = (lx + rx) / 2;

        rupd(l, r, v, 2 * x + 1, lx, mid);
        rupd(l, r, v, 2 * x + 2, mid, rx);

        merge(tr[x], tr[2 * x + 1], tr[2 * x + 2]);
    }

    void rupd(int l, int r, T v) {
        rupd(l, r + 1, v, 0, 0, siz);
    }

    data query(int l, int r, int x, int lx, int rx) {
        propagate(x, lx, rx);

        if (lx >= r or rx <= l) return d_neutral;
        if (lx >= l and rx <= r) return tr[x];

        int mid = (lx + rx) / 2;

        data curr;
        data left = query(l, r, 2 * x + 1, lx, mid);
        data right = query(l, r, 2 * x + 2, mid, rx);

        merge(curr, left, right);
        return curr;
    }

    data query(int l, int r) {
        return query(l, r + 1, 0, 0, siz);
    }
};

vector<vector<int>> a;
vector<pii> pos;
lazysegtree<int> st;
int n,m;

void upd(int i, int j, int add){
    // update the subsquare with corners (i,j),(i+1,j+1)
    vector<int> vals;
    for(int r = i; r <= i+1; ++r){
        for(int c = j; c <= j+1; ++c){
            vals.pb(a[r][c]);
        }
    }

    sort(all(vals));

    {
        int l = vals[0], r = vals[1]-1;
        st.rupd(l,r,add);
    }

    {
        int l = vals[2], r = vals[3]-1;
        if(l != inf1){
            st.rupd(l,r,add);
        }
    }
}

void give_initial_chart(int n_, int m_, std::vector<int> R, std::vector<int> C) {
    n = n_, m = m_;
    a = vector<vector<int>>(n+5,vector<int>(m+5,inf1));
    rep(i,n*m){
        int r = R[i]+1, c = C[i]+1;
        a[r][c] = i;
    }
    rep(i,n*m) pos.pb({R[i]+1,C[i]+1});

    st = lazysegtree<int>(n*m);
    st.build(n*m);

    rep(i,n+1){
        rep(j,m+1){
            upd(i,j,1);
        }
    }
}

int swap_seats(int x, int y) {
    auto [r1,c1] = pos[x];
    auto [r2,c2] = pos[y];
    set<pii> sqs;
    for(int i = r1-1; i <= r1; ++i){
        for(int j = c1-1; j <= c1; ++j){
            sqs.insert({i,j});
        }
    }
    for(int i = r2-1; i <= r2; ++i){
        for(int j = c2-1; j <= c2; ++j){
            sqs.insert({i,j});
        }
    }

    for(auto [i,j] : sqs){
        upd(i,j,-1);
    }

    swap(pos[x],pos[y]);
    swap(a[r1][c1],a[r2][c2]);

    for(auto [i,j] : sqs){
        upd(i,j,1);
    }

    auto [mn,mn_cnt] = st.query(0,n*m-1);
    assert(mn == 4);

    int ans = mn_cnt;
    return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 20 / 20
• Subtask 4: 6 / 6
• Subtask 5: 33 / 33
• Subtask 6: 30 / 30