Ruudukko

public class Main {

	public static void main(String[] args) {
		IO io = new IO();
		
		int n = io.nextInt();
		char[] characters = new char[n * n];
		
		for (int i = 0; i < n; i++) {
			char[] row = io.next().toCharArray();
			for (int j = 0; j < n; j++) {
				int index = j + i * n;
				characters[index] = row[j];
			}
		}
		
		int x = 0, y = 0;
		io.print(characters[0]);
		while(x < n - 1 || y < n - 1) {
			int right = Integer.MAX_VALUE;
			int down = Integer.MAX_VALUE;
			if(x < n - 1) {
				right = characters[(x + 1) + y * n];
			}
			if(y < n - 1) {
				down = characters[(x + n) + y * n];
			}
			if(right < down) {
				x++;
				io.print((char)right);
			} else {
				io.print((char)down);
				y++;
			}
			
		}
		
		io.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: WRONG ANSWER

Test 8

Group: 2

Verdict: WRONG ANSWER

Test 9

Group: 2

Verdict: WRONG ANSWER

Test 10

Group: 2

Verdict: WRONG ANSWER

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: WRONG ANSWER

Test 13

Group: 3

Verdict: WRONG ANSWER

Test 14

Group: 3

Verdict: WRONG ANSWER

Test 15

Group: 3

Verdict: WRONG ANSWER