Greatest element in a Multi-Dimensional Array in JavaScript

We have to write a simple function in JavaScript that takes in an array of Numbers (nested to any level) and return the greatest number present in the array.

For example:

If the input array is −

const arr = [
   34, 65, 67,
   [
      43, 76, 87, 23, 56, 7,
      [
         54, 7, 87, 23, 79, 994, 2
      ],
      54
   ], 54, 4, 2
];

Then the output should be −

994

We will use recursion to find the greatest number in the array,

Therefore, let’s write the code for this function −

Example

The code for this will be −

const arr = [
   34, 65, 67,
   [
      43, 76, 87, 23, 56, 7,
      [
         54, 7, 87, 23, 79, 994, 2
      ],
      54
   ], 54, 4, 2
];
const getGreatest = (arr, greatest = -Infinity) => {
   for(let i = 0; i < arr.length; i++){
      if(Array.isArray(arr[i])){
         return getGreatest(arr[i], greatest);
      };
      if(arr[i] > greatest){
         greatest = arr[i];
      }
   };
   return greatest;
};
console.log(getGreatest(arr));

Output

The output in the console will be −

994