How do I check if an array is in another array?

Question

Here, I have an array in Java, lose, that has two arrays inside of it: xLose and yLose.

    int[] xLose = selectLose(buttons, xNum);
    int[] yLose = selectLose(buttons, yNum);
    int[][] lose = {xLose, yLose};

I already have a method that can check if an element is an array:

public boolean isInArray(int num, int[] array)
{
    for (int i = 0; i < array.length; i++)
    {
        if(num == array[i])
        {
            return true;
        }
    }
    return false;
}

But how do I check if an array is an element of an array of arrays? For example, is xLose in lose?

You do the same thing, if you are testing identity. Just make `num` be `int[]` and make `array` be `int[][]`. — dsh, Aug 11 '15 at 18:09
num will never equal array[i] .... regardless of the language, you need to break up array[i] so that it looks at the first place holder (which is xlose) in array[i]... Right now this formulates to num == array[i] == {xLose,yLose} ... which will never be true. — Nefariis, Aug 11 '15 at 18:10
The isInArray is checking if a number is in a one-dimensional array. Why can't num == array[i]? array[i] is an int and num is an int also. — michaeljan, Aug 11 '15 at 18:16
possible duplicate of [Finding if an array contains all elements in another array](http://stackoverflow.com/questions/16524709/finding-if-an-array-contains-all-elements-in-another-array) — StefanHeimberg, Aug 11 '15 at 18:24

score 1 · Accepted Answer · answered Aug 11 '15 at 18:32

1

import java.util.Arrays;

public boolean isInArray(int[] sub, int[][] sup){
    for(int i=0; i<sup.length; i++)
        if(Arrays.equals(sub, sup[i]))
            return true;
    return false;
}

answered Aug 11 '15 at 18:32

Tony Tuttle

612
7
23

score 0 · Answer 2 · answered Aug 11 '15 at 18:35

0

Better use collection, there things are more simpler)

answered Aug 11 '15 at 18:35

Shell Scott

1,679
18
28

score 0 · Answer 3 · answered Aug 11 '15 at 18:52

you need to do something like this:

public boolean ArrayisInArray(int[] array1, int[][] array2)
{
    int cont=0;
    for (int i = 0; i < array2.length; i++)
    {          
      for (int j = 0; j < array2.length; i++)
      {
          if (array1[j]==array2[i][j])  
           cont++;

         if (cont == array1.length)
             return true;
      }
      cont=0;
    }
    return false;
}

this code can compare array1 with array2 row by row finding your first array in the second array

How do I check if an array is in another array?

3 Answers3