QuestionA.java

package Q17_24_Max_Submatrix;

import CtCILibrary.*;

public class QuestionA {
	public static SubMatrix getMaxMatrix(int[][] matrix) {
		int rowCount = matrix.length;
		int columnCount = matrix[0].length;
		SubMatrix best = null;
		for (int row1 = 0; row1 < rowCount; row1++) {
			for (int row2 = row1; row2 < rowCount; row2++) {
				for (int col1 = 0; col1 < columnCount; col1++) {
					for (int col2 = col1; col2 < columnCount; col2++) {
						int sum = sum(matrix, row1, col1, row2, col2);
						if (best == null || best.getSum() < sum) {
							best = new SubMatrix(row1, col1, row2, col2, sum);
						}
					}
				}
			}
		}
		return best;
	}
	
	private static int sum(int[][] matrix, int row1, int col1, int row2, int col2) {
		int sum = 0;
		for (int r = row1; r <= row2; r++) {
			for (int c = col1; c <= col2; c++) {
				sum += matrix[r][c];
			}
		}
		return sum;
	}
	
	public static void main(String[] args) {
		int[][] matrix = AssortedMethods.randomMatrix(10, 10, -5, 5);
		AssortedMethods.printMatrix(matrix);
		SubMatrix sub = getMaxMatrix(matrix);
		System.out.println(sub.toString());
	}

}