Largest rectangle of 1's in 2d binary matrix

Question

There is a problem to find the maximum area of the 1 in the 0-1 matrix. In this problem there are two cases:

1. area to be measure is of shape square. that\'s

Answer 1

**

//use this dynamic programming approach
//The problem can be reduced to finding the maximum rectangle area in a histogram, multiple times.
After each row, you calculate the histogram built until that row, and that calculate the maximum area rectangle in that histogram.

**

import java.util.Scanner;


public class LargestRectInAmatrix {
    static int row,col,matrix[][];
    static int maxArea=0;
    static int barMatrix[];
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        row=sc.nextInt();
        col=sc.nextInt();
        matrix=new int[row][col];
        barMatrix=new int[col];
        for(int i=0;imaxArea)
            {
                maxArea=area;
            }
        }

    }
    private static int calculateArea(int l,int h)
    {
        if(l>h)
        {
            return Integer.MIN_VALUE;
        }
        if(l==h)
        {
            return barMatrix[l];
        }
        int u=calMinimumIndex(l,h);
        return (max(calculateArea(l, u-1),calculateArea(u+1, h),barMatrix[u]*(h-l+1)));



    }
    private static int max(int a,int b,int c)
    {
        if(a>b)
        {
            if(a>c)
            {
                return a;
            }
            else
                return c;
        }
        else
            if(b>c)
            {
                return b;
            }
            else
                return c;
    }
    private static int calMinimumIndex(int l,int h)
    {
        int min=Integer.MAX_VALUE;
        int min_index=0;
        for(int i=l;l<=h;i++)
        {
            if(barMatrix[i]