Submission #874273

#	Time	Username	Problem	Language	Result	Execution time	Memory
874273		tsumondai	Dango Maker (JOI18_dango_maker)	C++14	100 / 100	293 ms	80344 KiB

dango_maker

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

#define int long long
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define foru(i, l, r) for(int i = l; i <= r; i++)
#define ford(i, r, l) for(int i = r; i >= l; i--)
#define __TIME  (1.0 * clock() / CLOCKS_PER_SEC)

typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;

const int N = 3000 + 5;

const int oo = 1e18, mod = 1e9 + 7;

int n, m, k, ans=0, dp[2*N][5];
int a[N][N]; // R G W

void process() {
	foru(tmp, 1, n+m) {
		memset(dp, 0, sizeof(dp));
		int i=1, j=tmp-1, cnt=1;
		while (i<=n && j>=1) {
			if (j>m) {
				i++; j--; continue;
			}
			dp[cnt][0]=max(dp[cnt-1][0], max(dp[cnt-1][1], dp[cnt-1][2]));
			if (a[i][j-1]==0 && a[i][j]==1 && a[i][j+1]==2) dp[cnt][1]=max(dp[cnt-1][0], dp[cnt-1][1])+1;
			if (a[i-1][j]==0 && a[i][j]==1 && a[i+1][j]==2) dp[cnt][2]=max(dp[cnt-1][0], dp[cnt-1][2])+1;
			i++; j--;
			cnt++;	
		}
		cnt--;
		ans+=max(dp[cnt][0], max(dp[cnt][1], dp[cnt][2]));
		//cout << dp[cnt][0] << ' ' << dp[cnt][1] << ' ' << dp[cnt][2] << '\n';
	}
	cout << ans << '\n';
	return;
}

signed main() {
	cin.tie(0)->sync_with_stdio(false);
	//freopen(".inp", "r", stdin);
	//freopen(".out", "w", stdout);
	cin >> n >> m;
	memset(a, -1, sizeof(a));
	foru(i, 1, n) foru(j, 1, m) {
		char x; 
		cin >> x; 
		if (x == 'R') a[i][j]=0;
		else if (x=='G') a[i][j]=1;
		else if (x=='W') a[i][j]=2;
	}

	process();
	cerr << "Time elapsed: " << __TIME << " s.\n";
	return 0;
}

/*
Xét các trường hợp đặc biệt
Kiểm tra lại input/output
Cố gắng trâu
Lật ngược bài toán
Calm down and get VOI
Stream of thought:
dp
*/

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