A method called indexOf2D that takes as arguments 2 2D arrays of integers called

Question

A method called indexOf2D that takes as arguments 2 2D arrays of integers called bigArray and smallArray, that implements for 2D arrays what indexOf1D does for 1D arrays of integers. It checks if smallArray is a "patch" of bigArray. If it is not, it returns -1. If it is a subarray, the method returns the row and column indexes of bigArray where smallArray starts. For example: if bigArray is: 3,1,5,7,2,3,1

4,1,7,2,8,5,0

1,2,3,9,0,2,1

and smallArrays is: 5,7,2,3

7,2,8,5

The method will return indexes 0 and 2. You cannot return 2 numbers as 2 separate entities. You must return them as an array of int or an ArrayList. If the small array is not a 'patch' of the bigArray, return -1 and -1.

Explanation / Answer

public class SearchArray {
   public static int[] indexOf2D(int[][] BigArray,int[][] SmallArray)
   {
       int[] b= new int[]{-1,-1};
       int row1 = BigArray.length;
       int col1 = BigArray[0].length;
       int row2 = SmallArray.length;
       int col2 = SmallArray[0].length;
       for(int i=0;i<=row1-row2;i++)
       {
           for(int j=0;j<col1-col2;j++)
           {
               if(comp(BigArray,SmallArray,i,j))
               {
                   b[0]=i;
                   b[1]=j;
                   return b;
               }
           }
       }
       return b;
   }
   private static boolean comp(int[][] bigArray, int[][] smallArray, int i, int j) {
       // TODO Auto-generated method stub
       boolean flag=true;
       int row2 = smallArray.length;
       int col2 = smallArray[0].length;
       for(int p=0;p<row2;p++)
       {
           for(int q=0;q<col2;q++)
           {
               if(smallArray[p][q]!=bigArray[i+p][j+q])
               {
                   return false;
               }
           }
       }
      
       return flag;
   }
   public static void main(String[] args)
   {
       int[][] Big = new int[][]{
           {3,1,5,7,2,3,1},
           {4,1,7,2,8,5,0},
           {1,2,3,9,0,2,1}
       };
       int[][] Small = new int[][]{
           {5,7,2,3},
           {7,2,8,5}
       };
       int[] c = indexOf2D(Big, Small);
       System.out.println(c[0]+" "+c[1]);

   }
}

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