Submission #925575

#	Time	Username	Problem	Language	Result	Execution time	Memory
925575		vjudge1	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	79 / 100	2054 ms	7260 KiB

mushrooms

// By ObeliX
#include <bits/stdc++.h>
#pragma GCC target( "sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#include <unordered_map>
#include <cstddef>
#include <cassert>
#include <bitset>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <cmath>
#include <queue>
#include <map>
#include <set>

using namespace std;

const long long N = 1e6 + 5;
const long long MOD = 1e7 + 7;
const long long inf = 1e18;

long long n , m , d , k;

int main(){
    //freopen( "cinema.in" , "r" , stdin );
    //freopen( "cinema.out" , "w" , stdout );
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m >> d >> k;
    char c[n+5][m+5];
    for ( int i = 0 ; i <= n + 1 ; i++ ) {
        for ( int j = 0 ; j <= m + 1 ; j++ ) {
            c[i][j] = '.';
        }
    }
    long long cnt1 = 0 , cnt2 = 0;
    for ( int i = 1 ; i <= n ; i++ ) {
        for ( int j = 1 ; j <= m ; j++ ) {
            cin >> c[i][j];
            if ( c[i][j] == 'S' ) {
                cnt1++;
            }
            if ( c[i][j] == 'M' ) {
                cnt2++;
            }
        }
    }
    if ( d == max( n , m ) && cnt1 >= k ) {
        cout << cnt2 ;
    }
    else {
        if ( d == 1 && k == 1 ) {
            long long ans = 0;
            for ( int i = 1 ; i <= n ; i++ ) {
                for ( int j = 1 ; j <= m ; j++ ) {
                    if ( c[i][j] == 'M' ) {
                        if ( c[i][j-1] == 'S' || c[i-1][j] == 'S' || c[i+1][j] == 'S' || c[i][j+1] == 'S' ||c[i+1][j-1] == 'S' ||c[i-1][j+1] == 'S' ||c[i-1][j-1] == 'S' ||c[i+1][j+1] == 'S') {
                            ans++;
                        }
                    }
                }
            }
            cout << ans;
        }
        else {
            if ( n == 1 ) {
                long long scan[m+5];
                for ( int i = 0 ; i <= m ; i++ ) {
                    scan[i] = 0;
                }
                for ( int i = 1 ; i <= m ; i++ ) {
                    if ( c[1][i] == 'S' ) {
                        scan[min( m + 1 , i + d + 1 )]--;
                        scan[max( 1ll , i - d )]++;
                    }
                }
                long long ans = 0;
                for ( int i = 1 ; i <= m ; i++ ) {
                    scan[i] += scan[i-1];
                    if ( c[1][i] == 'M' && scan[i] >= k ) {
                        ans++;
                    }
                }
                cout << ans;
            }
            else {
                vector <pair<long long , long long>> v1 , v2;
                for ( int i = 1 ; i <= n ; i++ ) {
                    for ( int j = 1 ; j <= m ; j++ ) {
                        if ( c[i][j] == 'M' ) {
                            v2.push_back( { i , j } );
                        }
                        else if ( c[i][j] == 'S' ) {
                            v1.push_back( { i , j } );
                        }
                    }
                }
                long long ans = 0;
                for ( auto it : v2 ) {
                    long long x = it.first , y = it.second;
                    long long cnt = 0;
                    for ( auto it1 : v1 ) {
                        long long x1 = it1.first , y1 = it1.second;
                        if ( max( abs( x - x1 ) , abs( y1 - y ) ) <= d ) {
                            cnt++;
                        }
                    }
                    if ( cnt >= k ) {
                        ans++;
                    }
                }
                cout << ans ;
            }
        }
    }
}

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 18 / 18
• Subtask 4: 23 / 23
• Subtask 5: 19 / 19
• Subtask 6: 0 / 21