Submission #862192

#	Time	Username	Problem	Language	Result	Execution time	Memory
862192		3omar_ahmed	Kamenčići (COCI21_kamencici)	C++17	70 / 70	98 ms	344776 KiB

Main

#include <bits/stdc++.h>
using namespace std ;
#define int long long
#define endl '\n'
#define all(a) a.begin() , a.end()
#define alr(a) a.rbegin() , a.rend()

int n, k;
string x;
vector < int > pre, suf;

int dp[353][353][353];

int solve(int l, int r, int red) {
    int type = ((l - 1) + (n - r)) % 2;
    if(red == k) {
        return 0;
    }
    int opp = pre[l - 1] + suf[r + 1] - red;
    if(opp == k) {  
        return 1;
    }
    if(dp[l][r][red] != -1) return dp[l][r][red]; 
    dp[l][r][red] = 0;
    if(type == 0) {
        if(solve(l + 1, r, red + (x[l] == 'C')))
            return dp[l][r][red] = 1;
        if(solve(l, r - 1, red + (x[r] == 'C')))
            return dp[l][r][red] = 1;
        return 0;
    } else {
        if(!solve(l + 1, r, red))
            return 0;
        if(!solve(l, r - 1, red))
            return 0;
        return dp[l][r][red] = 1;
    }
}

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);cout.tie(0);

    cin >> n >> k >> x;
    pre = suf = vector < int > (n + 2);
    x = "%" + x;
    for(int i = 1 ; i <= n ; i++) {
        pre[i] = pre[i - 1] + (x[i] == 'C');
    }
    for(int i = n ; i >= 1 ; i--) {
        suf[i] = suf[i + 1] + (x[i] == 'C');
    }
    memset(dp, -1, sizeof(dp));
    if(solve(1, n, 0)) {
        cout << "DA" << endl; 
    } else {
        cout << "NE" << endl;
    }
    return 0 ;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 40 / 40