Question

How to group elements of an array based on their first occurrence in JavaScript

Answer 1

function group_elements(arr) {
	let frequency = new Array(10).fill(0);
   
    for (let i = 0; i < arr.length; i++) {
        frequency[arr[i]]++;
    }
   
    for (let i = 0; i < arr.length; i++) {
        if (frequency[arr[i]] != 0) {
            let total_frequency = frequency[arr[i]];
            while (total_frequency--) {
                console.log(arr[i]);
            }
            frequency[arr[i]] = 0;
        }
    }
}

const arr = [8, 3, 7, 8, 2, 5, 8, 5, 1, 9, 8, 1, 7];

group_elements(arr);




/*
run

8
8
8
8
3
7
7
2
5
5
1
1
9

*/

 

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