Jshacker

14/01/2019

Sorted array find a pair of sum

function arrayPairSum(arr, k){
let left =0; let right = arr.length -1;
let result = [];
while(left < right){
let sum = arr[left] + arr[right];
console.log(sum);
if(k == sum){
result = [arr[left], arr[right]];
left+=1;
}else if(k > sum){
left+=1;
}else{
right-=1;
}
}
return result;
}

arrayPairSum([1,2,3,5,6,7,8,11,15],13); // [6,7]

07/09/2018

Write a function to reverse a positive integer?

function reverseNumber(num){
let rev = 0;
let rem;

while(num > 0){
rem = num % 10;
rev = rev * 10 + rem;
num = Math.floor(num/10);
}

return rev
}

console.log(reverseNumber(123)); // output: 321😉

Java Script Hacker

05/09/2018

Write a function to merge intervals.

Story:
Your company built an in-house calendar tool called HiCal. You want to add a feature to see the times in a day when everyone is available.

You receive the array of meetings with startTime, endTime and now you need to merge the intervals between meetings and show the end result.

Ex: Meetings Array : [{ startTime: 0, endTime: 1 }, { startTime: 3, endTime: 5 }, { startTime: 4, endTime: 8 }, { startTime: 10, endTime: 12 }, { startTime: 9, endTime: 10 }]

your function should return : [ { startTime: 0, endTime: 1 },
{ startTime: 3, endTime: 8 },
{ startTime: 9, endTime: 12 } ];

Answer :

var meetings = [{ startTime: 0, endTime: 1 }, { startTime: 3, endTime: 5 }, { startTime: 4, endTime: 8 }, { startTime: 10, endTime: 12 }, { startTime: 9, endTime: 10 }]

function merge_overlaping_intervals(arr) {
// if (arr.length a.startTime > b.startTime);
let result = [];
result.push(s[0]);

for (let i = 1; i < s.length; i++) {
let top = result[result.length - 1];
if (top.endTime < s[i].startTime) {
result.push(s[i]);
} else if (top.endTime < s[i].endTime) {
top.endTime = s[i].endTime;
}
}

return result;
}

console.log(merge_overlaping_intervals(meetings));

01/09/2018

Write a recursive function to sum the elements of an array?

function arrSum(arr) {
if (arr.length == 1) return arr[0];
return arr[0] + arrSum(arr.slice(1));
}

console.log(arrSum([10, 2, 3, 1, 4]));

05/06/2018

Bubble Sort in JavaScript: Big O(n*n)

31/05/2018

Problem: Print a given matrix in a spiral form
Solution:

18/08/2017

Problem:
Find a combination of the numbers in a unsorted array which are equals to sum using JS.

Solution:

17/08/2017

https://www.smashingmagazine.com/2017/08/ai-chatbot-web-speech-api-node-js/

In this tutorial, we will use the API to create an artificial intelligence (AI) voice chat interface in the browser. The app will listen to the user’s voice and reply with a synthetic voice.

13/03/2016

JavaScript programmers like to use words like, “event-loop”, “non-blocking”, “callback”, “asynchronous”, “single-threaded” and “concurrency”. We say things l...

04/11/2015

Q : Print A to Z alphabets without using loops.

var printAlphabets = function(c){
c = c || 97; // 97 is a
if(c < 123){
console.log(String.fromCharCode(c++));
printAlphabets(c);
}
}

26/09/2015

Find non repeated number in an array

var ar = [1,2,3,4,5,5,4,3,1],
num = 0;

for(var i =0; i

26/09/2015

Promise visualization playground for the adventurous