EG-13_Sprint-1_PS.js

// 01. Check if a Year is a Leap Year
function isLeapYear(year) {
    return (year % 4 === 0 && year % 100 !== 0) || (year % 400 === 0);
}
console.log("1. Leap Year:", isLeapYear(2024));

// 02. Generate Fibonacci Sequence Up to N Terms
function generateFibonacci(n) {
    if (n <= 0) return [];
    if (n === 1) return [0];
    
    const fib = [0, 1];
    for (let i = 2; i < n; i++) {
        fib.push(fib[i - 1] + fib[i - 2]);
    }
    return fib;
}
console.log("02. Fibonacci Sequence:", generateFibonacci(7));

// 03. Calculate the Greatest Common Divisor (GCD)
function findGCD(a, b) {
    let x = Math.abs(a);
    let y = Math.abs(b);
    while (y) {
        const temp = y;
        y = x % y;
        x = temp;
    }
    return x;
}
console.log("3. GCD:", findGCD(48, 18));

// 04. Calculate the Least Common Multiple (LCM)
function findLCM(a, b) {
    if (a === 0 || b === 0) return 0;
    return Math.abs(a * b) / findGCD(a, b);
}
console.log("4. LCM:", findLCM(12, 18));

// 05. Check if a Number is Prime
function isPrime(num) {
    if (num <= 1) return false;
    if (num <= 3) return true;
    if (num % 2 === 0 || num % 3 === 0) return false;
    
    for (let i = 5; i * i <= num; i += 6) {
        if (num % i === 0 || num % (i + 2) === 0) return false;
    }
    return true;
}
console.log("5. Prime Check:", isPrime(29));

// 06. Merge Two Sorted Arrays into One Sorted Array
function mergeSortedArrays(arr1, arr2) {
    const merged = [];
    let i = 0;
    let j = 0;

    while (i < arr1.length && j < arr2.length) {
        if (arr1[i] <= arr2[j]) {
            merged.push(arr1[i]);
            i++;
        } else {
            merged.push(arr2[j]);
            j++;
        }
    }

    while (i < arr1.length) {
        merged.push(arr1[i]);
        i++;
    }

    while (j < arr2.length) {
        merged.push(arr2[j]);
        j++;
    }

    return merged;
}
console.log("6. Merge Sorted Arrays:", mergeSortedArrays([1, 3, 5], [2, 4, 6]));

// 07. Find the Median of an Unsorted Array
function findMedian(nums) {
    if (!nums || nums.length === 0) return 0;
    
    const sorted = [...nums].sort((a, b) => a - b);
    const mid = Math.floor(sorted.length / 2);

    if (sorted.length % 2 !== 0) {
        return sorted[mid];
    }
    return (sorted[mid - 1] + sorted[mid]) / 2;
}
console.log("7. Median:", findMedian([7, 1, 3, 4, 9]));

// 08. Find the Second Largest Number in an Array
function findSecondLargest(nums) {
    let max = -Infinity;
    let secondMax = -Infinity;

    for (const num of nums) {
        if (num > max) {
            secondMax = max;
            max = num;
        } else if (num > secondMax && num < max) {
            secondMax = num;
        }
    }

    return secondMax === -Infinity ? null : secondMax;
}
console.log("8. Second Largest:", findSecondLargest([10, 20, 4, 45, 99, 99]));

// 09. Find Most Frequent Element (Mode) in an Array
function findMode(arr) {
    if (!arr || arr.length === 0) return null;

    const frequencyMap = new Map();
    let maxCount = 0;
    let mode = null;

    for (const item of arr) {
        const count = (frequencyMap.get(item) || 0) + 1;
        frequencyMap.set(item, count);

        if (count > maxCount) {
            maxCount = count;
            mode = item;
        }
    }

    return mode;
}
console.log("9. Mode Value:", findMode([1, 3, 3, 2, 1, 3, 4]));

// 10. Natural Sorting of Strings with Embedded Numbers
function naturalSort(arr) {
    return [...arr].sort((a, b) => 
        a.localeCompare(b, undefined, { numeric: true, sensitivity: 'base' })
    );
}
console.log("10. Natural Sort:", naturalSort(["file10.txt", "file2.txt", "file1.txt"]));