Hackerrank Challenge: https://www.hackerrank.com/challenges/migratory-birds/problem?isFullScreen=true

migratoryBirds.js

function migratoryBirds(arr) {
    // Write your code here
    let countA = 0;
    let countB = 0;
    let countC = 0;
    let countD = 0;
    let countE = 0;
    for (let item of arr) {
        switch (item) {
            case 1: countA++;
            break;
            case 2: countB++;
            break;
            case 3: countC++;
            break;
            case 4: countD++;
            break;
            case 5: countE++;
            break;
            default: null;
        }
    }
    const maxVal = Math.max(countA, countB, countC, countD, countE);
    let countArr = [ {value: 1, count: countA}, {value: 2, count: countB}, {value: 3, count: countC}, {value: 4, count: countD}, {value: 5, count: countE}];
    const newCount = countArr.filter(item => item.count === maxVal );
    
    if (newCount.length > 1) {
        const newArr = newCount.map(item => item.value);
        return Math.min(...newArr);
    } else {
        return newCount[0].value;
    }

}