Tontti

public class Tonts2 {
	static int width, height, treesWanted;
	static char[][] chr;
	
	static int[][] arr;
	
	public static void main(String[] args) {
		IO oi = new IO();
		
		height = oi.nextInt();
		width = oi.nextInt();
		treesWanted = oi.nextInt();
		
		chr = new char[height][];
		arr = new int[height][];
		
		for(int i = 0; i < height; i++) {
			chr[i] = oi.next().toCharArray();
			arr[i] = new int[width];
		}
		
		int minScope = (int) Math.ceil(Math.sqrt(treesWanted)),
				maxScope = height < width ? height : width;
		
		for(int y = 0; y < height; y++) {
			arr[y][0] = chr[y][0] == '*' ? 1 : 0;
			
			for(int x = 1; x < width; x++)
				arr[y][x] = arr[y][x-1] + (chr[y][x] == '*' ? 1 : 0);
			
			for(int x = 0; x < width; x++)
				if(y > 0) arr[y][x] += arr[y-1][x];
		}
		
		int valA, val1, val2, val3;
		int result = 0;
		
		for(int scope = minScope; scope <= maxScope; scope++) {
			for(int y = 0; y <= height - scope; y++) {
				for(int x = 0; x <= width - scope; x++) {
					valA = arr[y+scope-1][x+scope-1];
					val1 = x > 0 && y > 0 ? arr[y-1][x-1] : 0;
					val2 = y > 0 ? arr[y-1][x+scope-1] : 0;
					val3 = x > 0 ? arr[y+scope-1][x-1] : 0;
					
					if(valA - val1 - (val2 - val1) - (val3 - val1) == treesWanted)
						result++;
				}
			}
		}
		
		oi.println(result);
		oi.close();
	}
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED