# Equality of two 2-D arrays - JavaScript

We are required to write a JavaScript function that takes in two 2-D arrays and returns a boolean based on the check whether the arrays are equal or not.

The equality of these arrays, in our case, is determined by the equality of corresponding elements

Both the arrays should have same number of rows and columns −

arr1[i][j] === arr2[i][j]

The above should yield true for all i between [0, number of rows] and j between [0, number of columns]

## Example

Let’s write the code for this function −

const arr1 = [
[1, 1, 1],
[2, 2, 2],
[3, 3, 3],
];
const arr2 = [
[1, 1, 1],
[2, 2, 2],
[3, 3, 3],
];
const areEqual = (first, second) => {
const { length: l1 } = first;
const { length: l2 } = second;
if(l1 !== l2){
return false;
};
for(let i = 0; i < l1; i++){
for(j = 0; j < first[i].length; j++){
if(first[i][j] !== second[i][j]){
return false;
};
};
};
return true;
};
console.log(areEqual(arr1, arr2));

## Output

The output in the console −

true

Updated on: 15-Sep-2020

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