how to Find the maximum number in a jagged array given below array of numbers?

Question

how to Find the maximum number in a jagged array given below array of numbers?

const array= [2,4,10,[12,4,[100,99],4],[3,2,99],0];

Answer 1

If you know the maximum depth of nesting, then you can flat the array and find the maximum:

Math.max(...array.flat(depth));

If you don't know the maximum depth, you need to iterate over all the items recursively:

const findMax = item => Math.max(...item.map(row => Array.isArray(row) ? findMax(row) : row));

console.log(findMax([2,4,10,[12,4,[100,99],4],[3,2,99],0]));

Answer 2

You can flat the jagged array using flat method and after that find max in it. like:

const array = [2,4,10,[12,4,[100,99],4],[3,2,99],0];
const flatArray = array.flat(2);
console.log("Max Value is "+ Math.max(...flatArray));

Answer 3

if you don't know the level of depth

let array = [2, 4, 10, [12, 4, [100, 99], 4], [3, 2, 99], 0 ]

let max = 0

function maxNumber(array) {
  for (let i = 0; i < array.length; i++) {
    if (Array.isArray(array[i])) {
      maxNumber(array[i])
    } else {
      if (array[i] > max) {
        max = array[i]
      }
    }
  }
}
maxNumber(array)
console.log(max)

Answer 4

You could reduce the array and check if the value is an array, then reduce this array or take the value for the wanted function.

const
    reduceBy = fn => {
        const r = array => array.reduce((a, b) => fn(
            Array.isArray(a) ? r(a) : a,
            Array.isArray(b) ? r(b) : b
        ));
        return r;
    },
    array = [2, 4, 10, [12, 4, [100, 99], 4], [3, 2, 99], 0],
    result = reduceBy(Math.max)(array);

console.log(result);

Answer 5

var arr = [2, 4, 10, [12, 4, [100, 99], 4], [(3, 2, 99)], 0];
function getMax(a) {
    return Math.max(...a.map((e) => (Array.isArray(e) ? getMax(e) : e)));
}
console.log(getMax(arr));