Submission #571692

#	Time	Username	Problem	Language	Result	Execution time	Memory
571692		SlavicG	Painting Walls (APIO20_paint)	C++17	0 / 100	1 ms	300 KiB

paint

#include "bits/stdc++.h"
using namespace std;
 
#define ll long long
 
#define       forn(i,n)              for(int i=0;i<n;i++)
#define          all(v)              v.begin(), v.end()
#define         rall(v)              v.rbegin(),v.rend()
 
#define            pb                push_back
#define          sz(a)               (int)a.size()

const int K = 18;

int minimumInstructions(int n, int m, int k, vector<int> c, vector<int> a, vector<vector<int>> b) {
    vector<int> p[k + 1];
    set<int> st[2 * n + 5][K];
    map<pair<int, int>, bool> mp;
    for(int i = 0; i < m; ++i) {
        for(auto x: b[i]) {
            p[x].pb(i);
            mp[{i, x}] = 1;
        }
    }

    
    for(int i = 0; i < n; ++i) {
        for(auto x: p[c[i]]) {
            st[i][0].insert(x);
        }
    }

    for(int j = 1; j < K; ++j) {
        for(int i = 0; i + (1 << j) <= n; ++i) {
            for(auto x: st[i][j - 1]) {
                if(st[i + (1 << j)][j - 1].count((x + (1 << j)) % m)) {    
                    st[i][j].insert(x);
                }
            }
        }
    }
    
    vector<bool> can(n, false);

    for(int i = 0; i + m - 1 < n; ++i) {
        for(int x = 0; x < m; ++x) {
            int cur = x;
            int idx = i;
            bool ok = true;
            for(int j = K - 1; j >= 0; --j) {
                if(m & (1 << j)) {
                    if(!st[idx][j].count(cur)) {
                        ok = false;
                        break;
                    }
                    cur = (cur + (1 << j)) % m;
                    idx += (1 << j);
                    assert(idx <= n);
                }
            }
            if(ok) {
                assert(idx == i + m);
                can[i] = true;
                break;
            }
        }
    }


    /*
    for(int i = 0; i + m - 1 < n; ++i) {
        for(int x: p[c[i]]) {
            bool ok = true;
            for(int times = 0; times < m && ok; ++times) {
                if(!mp[{(x + times) % m, c[i + times]}]) ok = false;
            }
            if(ok) {
                can[i] = true;
                break;
            }
        }
    }
    */

    set<int> good;
    forn(i, n) if(can[i]) good.insert(i); 
    int lst = -1e9, ans = 0;
    for(int i = 0; i < n; ++i) {
        if(lst + m - 1 >= i) continue;
        ++ans;
        if(can[i]) {
            lst = i;
        } else {
            auto it = good.lower_bound(i);
            if(it == good.begin()) return -1;
            --it;
            if(*it + m - 1 < i) return -1;
            lst = *it;
        }
    }
    return ans;
}

/*

void solve() {  
    
} 
     
int32_t main() {
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int t = 1;
    //cin >> t;
    while(t--) {
        solve();
    }
}   
*/

• Subtask 1: 0 / 12
• Subtask 2: 0 / 15
• Subtask 3: 0 / 13
• Subtask 4: 0 / 23
• Subtask 5: 0 / 37