47 lines
1.3 KiB
Java
47 lines
1.3 KiB
Java
// Author: Rodney Shaghoulian
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// Github: github.com/RodneyShag
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// HackerRank: hackerrank.com/RodneyShag
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import java.util.Scanner;
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import java.util.Arrays;
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public class Solution {
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public static void main(String[] args) {
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Scanner scan = new Scanner(System.in);
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int T = scan.nextInt();
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while (T-- > 0) {
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int N = scan.nextInt();
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char [][] grid = new char[N][N];
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for (int i = 0; i < N; i++) {
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String str = scan.next();
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for (int j = 0; j < str.length(); j++) {
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grid[i][j] = str.charAt(j);
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}
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}
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System.out.println(canConvert(grid) ? "YES" : "NO");
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}
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scan.close();
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}
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/* Uses Greedy Approach */
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private static boolean canConvert(char [][] grid) {
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/* Sort each row */
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int rows = grid.length;
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int cols = grid[0].length;
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for (int row = 0; row < rows; row++) {
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Arrays.sort(grid[row]);
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}
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/* Check columns for lexicographic ordering */
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for (int row = 1; row < rows; row++) {
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for (int col = 0; col < cols; col++) {
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if (grid[row][col] < grid[row-1][col]) {
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return false;
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}
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}
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}
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return true;
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}
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}
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