Array logics

 Array logics:


1. Write a program to print the smallest number in an array?


function lowestElement(arr) {
        for (let j = arr.length-1; j > 0; j--) {
            if(arr[j] < arr[j-1]) {
                var temp = arr[j]; 
                arr[j] = arr[j-1];
                arr[j-1] = temp;
            }            
        }
    console.log(arr[0]);
    
}
The above program is based on the bubble sorting logic, sending the lower element to first place.

function smallestNumberWithSelectionSort(arr) {
    var lowest = 0;
    for (let i = 1; i < arr.length; i++) {
        if(arr[i] < arr[lowest]) {
            lowest = i;
        }
    }
    if(lowest !== 0) {
        var temp = arr[lowest];
        arr[lowest] = arr[0];
        arr[0] = temp;
    }
    console.log(arr);
}

smallestNumberWithSelectionSort([34, 22, 12, 44, 9, 99]);

lowestElement([5,1,2,3,4]);

2. Write a program to print the largest number in an array?


function highestElement(arr) {
        for (let j = 1; j < arr.length; j++) {

            if(arr[j] > arr[j+1]) {
                var temp = arr[j];
                arr[j] = arr[j+1];
                arr[j+1] = temp;
            }
            
        }
    console.log(arr[arr.length-1]);
    
}
The above program is based on the bubble sorting logic, sending the large element to the last place.

highestElement([12,22,33,1,2,3,99,4,5,6]);

3. Write a program to merge two sorted arrays?

This is for sorted arrays only

function mergeSortedArrays(arr1, arr2) {

    let mergedArray = [];
    let i = 0; 
    let j = 0;
    
// take 2 arrays in a loop
    while (i < arr1.length && j < arr2.length) {
// Compare it's index elements and push the lower element to result array and increase the index of array, which we have taken element from
        if(arr1[i] < arr2[j]) {
            mergedArray.push(arr1[i]);
            i++;
        } else {
            mergedArray.push(arr2[j]);
            j++;
        }
    }
    
// If the 2 arrays are not same in length, then we need to push remaining elements to list
    while (i < arr1.length) {
        mergedArray.push(arr1[i]);
        i++;
    }
    while (j < arr2.length) {
        mergedArray.push(arr2[j]);
        j++;
    }
    console.log(mergedArray);
}

mergeSortedArrays([1,2,3,13, 5], [6,7,8,9]);






































Comments

Post a Comment

Popular posts from this blog

Selection Sort

  Selection Sort Finding(selecting) the smallest element in the loop and swapping it to the starting of the unsorted array. This is best used for finding the smallest element in the array. Let's take an array We will write the outer loop Let's assume the first index of outer loop as smallest(lowest) number Now write the inner loop, and start the inner loop as i+1. Because we need to compare two adjacent elements, hence inner loop starts with i+1 Now after the inner loop, compare the lowest element with current inner loop element. If the inner loop element is lower than lowest element, then reassign lowest number index to j value. After completing the inner loop, check the lowest index value is changed or not If it changed, swap the lowest element index with outer loop index. function selectionSort (arr) {     for (let i = 0; i < arr.length; i++) {         var lowest = i;         for (let j = i + 1; j < arr.length; j++) { ...
Read more

Numbers programs

 1. Write a program to find the sum of natural numbers? function addUpToNumber(n) {     var total = 0;     for(let i = 1; i <= n; i++) {         total = total + i;     }     return total; }     addUpToNumber(4); 2. Write a program to find the sum of natural numbers without loop? function addUpToNumber(n) {     return n * (n+1)/2 } addUpToNumber(4); 3. Write a program to find the sum of even numbers? function sumOfFirstEvenNumbers(n) {     return n * (n+1) }     sumOfFirstEvenNumbers (4);  4. Write a program to find the sum of even numbers in a range?   function sumOfEvenNumbersBetweenRange(i, n) {     var result = 0;     for (let index = i; index <= n; index++) {         if(index % 2 == 0) {             result = result + index;             console.log(result);   ...
Read more

Merge Sort

Image
 Merge Sort We need to break the array into two halves. Once u break the array into two halves, u need to break those two separate halves into 2 more halves, a total of 4.  Like this, we need to break the array, where the individual array will have only one element using recursion. Once the array is broken into tiny pieces, we will join them again by merging them together. To achieve this, first we need to write a program to merge two sorted arrays.
Read more