Submission #1308212

#	Time	Username	Problem	Language	Result	Execution time	Memory
1308212		olizarowskib	Parking (CEOI22_parking)	C++20	4 / 100	1053 ms	138904 KiB

Main

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define int ll
#define ft first
#define sc second
#define pb push_back
#define all(x) x.begin(), x.end()
#define pi pair<int, int>
#define vi vector<int>
#define tii tuple<int, int, int>
#define tiii tuple<int, int, int, int>
#define tiiii tuple<int, int, int, int, int>
#define vpi vector<pi>
#define vtii vector<tii>
#define vtiii vector<tiii>

const int N = (1 << 20), MOD = 1e9 + 7, INF = int(1e18);

int arr[N], poz[N];

vpi ans;

bool vis[N];
int cnt, e;

int md(int x, int m){
    if(x == m) return x;
    if(x == 2 * m) return m;
    return x % m;
}
void mv(int x, int p, int m, int n){
    p = md(p, m);
    int v = md(poz[x], m);
    if(poz[x] > m) e = v;
    ans.pb({v, p});
    if(arr[p + m] == 0){
        arr[p + m] = x;
        arr[poz[x]] = 0;
        poz[x] = p + m;
    }else{
        arr[p] = x;
        arr[poz[x]] = 0;
        poz[x] = p;
        vis[md(x, n)] = 1;
        cnt--;
    }
}

bool check_clr(int c, int n, int m){
    c = md(c, n);
    if(vis[c]) return 1;
    int a = c, b = c + n;
    if(poz[a] > poz[b]) swap(a, b);
    int x = poz[a], y = poz[b];
    if(x > m && arr[x - m] != 0) return 0;
    if(y > m && arr[y - m] != 0) return 0;
    if(y <= m) return 0;
    mv(a, y, m, n);
    if(x <= m){
        check_clr(md(arr[x + m], n), n, m);
    }
    return 1;
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL); cout.tie(NULL);
    // random_device rd;
    // mt19937_64 gen(rd());
    int n, m;
    cin >> n >> m;
    cnt = n;
    for(int i = 1; i <= m; i++){
        cin >> arr[i + m] >> arr[i];
        if(vis[arr[i]]) arr[i] += n;
        if(arr[i] != 0) vis[arr[i]] = 1;
        if(vis[arr[i + m]]) arr[i + m] += n;
        vis[arr[i + m]] = 1;
        poz[arr[i]] = i;
        poz[arr[i + m]] = i + m;
        vis[0] = 0;
    }

    for(int i = 1; i <= n; i++){
        if(poz[i] % m != poz[i + n] % m) vis[i] = 0;
        else cnt--;
    }
    for(int i = 1; i <= n; i++){
        if(!vis[i]) check_clr(i, n, m);
    }
    e = -1;
    int r = -1;
    for(int i = 1; i <= m; i++){
        if(arr[i + m] == 0){
            e = r = i;
            break;
        }
    }
    vis[0] = 1;
    while(cnt > 0){
        int akt = -1, pom;
        for(int i = 1; i <= m; i++){
            if(arr[i + m] == 0){
                e = r = i;
                break;
            }
        }
        if(e == -1){
            cout << "-1\n";
            return 0;
        }
        for(int i = 1; i <= n; i++){
            if(poz[i] <= m && poz[i + n] <= m){
                akt = i;
                break;
            }
            if(!vis[i]) pom = i;
        }
        if(akt == -1) akt = pom;
        int x = poz[akt];
        mv(akt, e, m, n);
        check_clr(akt, n, m);
        if(x <= m) check_clr(arr[x + m], n, m);
        if(arr[e + m] != 0){
            for(int i = r + 1; i <= m; i++){
                if(arr[i + m] == 0){
                    e = r = i;
                    break;
                }
            }
            if(arr[e + m] != 0){
                e = -1;
            }
        }
    }

    cout << int(ans.size()) << "\n";
    // for(auto [i, j] : ans) cout << i << ' ' << j << "\n";

    return 0;
}

• Subtask 1: 2 / 10
• Subtask 2: 2 / 10
• Subtask 3: 0 / 25
• Subtask 4: 0 / 15
• Subtask 5: 0 / 25
• Subtask 6: 0 / 15