Submission #291705

#	Time	Username	Problem	Language	Result	Execution time	Memory
291705		reymontada61	Dango Maker (JOI18_dango_maker)	C++14	100 / 100	759 ms	80012 KiB

dango_maker

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

const int MXN = 3005;
int n, m;
int grid[MXN][MXN];
int can[MXN][MXN];
int dp[MXN][3];

signed main() {

	cin >> n >> m;
	for (int i=1; i<=n; i++) {
		string s;
		cin >> s;
		for (int j=1; j<=m; j++) {
			if (s[j-1] == 'R') grid[i][j] = 1;
			if (s[j-1] == 'G') grid[i][j] = 2;
			if (s[j-1] == 'W') grid[i][j] = 3;
		}
	}
	
	
	for (int i=1; i<=n; i++) {
		for (int j=1; j<=m; j++) {
			if (grid[i][j] == 2) {
				if (grid[i-1][j] == 1 && grid[i+1][j] == 3) {
					can[i][j] += 1;
				}
				if (grid[i][j-1] == 1 && grid[i][j+1] == 3) {
					can[i][j] += 2;
				}
			}
		}
	}
	
	int ans = 0;
	
	for (int diag=2; diag<=n+m; diag++) {
		dp[0][0] = dp[0][1] = dp[0][2] = 0;
		int here = 0;
		vector<int> vc;
		vc.push_back(-1);
		for (int i=1; i<=n; i++) {
			int j = diag - i;
			if (j >= 1 && j <= m) {
				vc.push_back(can[i][j]);
			}
		}
		for (int i=1; i<vc.size(); i++) {
			dp[i][0] = dp[i][1] = dp[i][2] = 0;
			dp[i][0] = max(max(dp[i-1][0], dp[i-1][1]), dp[i-1][2]);
			if (vc[i] & 1) {
				dp[i][1] = max(dp[i][1], 1 + max(dp[i-1][0], dp[i-1][1]));
			}
			if (vc[i] & 2) {
				dp[i][2] = max(dp[i][2], 1 + max(dp[i-1][0], dp[i-1][2]));
			}
			here = max(here, max(max(dp[i][0], dp[i][1]), dp[i][2]));
		}
		ans += here;
	}
	
	cout << ans << endl;
	
}

Compilation message (stderr)

dango_maker.cpp: In function 'int main()':
dango_maker.cpp:50:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |   for (int i=1; i<vc.size(); i++) {
      |                 ~^~~~~~~~~~

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