Submission #468363

#	Time	Username	Problem	Language	Result	Execution time	Memory
468363		JovanB	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	162 ms	21660 KiB

dango_maker

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ld = long double;

const int N = 3000;

string s[N+5];
int dp[N+5][3];

int main(){
    ios_base::sync_with_stdio(false), cin.tie(0);
    cout.precision(10);
    cout << fixed;

    int n, m;
    cin >> n >> m;
    for(int i=1; i<=m; i++) s[0] += ".";
    for(int i=1; i<=n; i++){
        string str;
        cin >> str;
        s[i] = "." + str;
        s[i] += ".";
    }
    for(int i=1; i<=m; i++) s[n+1] += ".";
    int res = 0;
    dp[0][1] = dp[0][2] = -N;
    for(int si=1; si<=n; si++){
        int i = si, j = 1;
        while(i > 0 && j <= m){
            dp[j][0] = max(dp[j-1][0], max(dp[j-1][1], dp[j-1][2]));
            if(s[i-1][j] == 'R' && s[i][j] == 'G' && s[i+1][j] == 'W') dp[j][1] = 1 + max(dp[j-1][0], dp[j-1][1]);
            else dp[j][1] = -N;
            if(s[i][j-1] == 'R' && s[i][j] == 'G' && s[i][j+1] == 'W') dp[j][2] = 1 + max(dp[j-1][0], dp[j-1][2]);
            else dp[j][2] = -N;
            i--;
            j++;
        }
        res += max(dp[j-1][0], max(dp[j-1][1], dp[j-1][2]));
    }
    for(int sj=2; sj<=m; sj++){
        int i = n, j = sj;
        dp[sj-1][0] = 0;
        dp[sj-1][1] = dp[sj-1][2] = -N;
        while(j <= m && i > 0){
            dp[j][0] = max(dp[j-1][0], max(dp[j-1][1], dp[j-1][2]));
            if(s[i-1][j] == 'R' && s[i][j] == 'G' && s[i+1][j] == 'W') dp[j][1] = 1 + max(dp[j-1][0], dp[j-1][1]);
            else dp[j][1] = -N;
            if(s[i][j-1] == 'R' && s[i][j] == 'G' && s[i][j+1] == 'W') dp[j][2] = 1 + max(dp[j-1][0], dp[j-1][2]);
            else dp[j][2] = -N;
            i--;
            j++;
        }
        res += max(dp[j-1][0], max(dp[j-1][1], dp[j-1][2]));
    }
    cout << res << "\n";
    return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 67 / 67