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Ashish donga
Ashish donga

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Top 7 best Algorithms to Improve your JavaScript Skills๐Ÿš€ ๐Ÿš€

Today I will teach you top 7 best algorithms to improve your JavaScript skills

best Algorithms to Improve JavaScript Skills as programmer

so let's start to understand JavaScript algorithms

1. how to Find the missing number from the array

const find_missing = function(input) {
  let n = input.length + 1;
let sum = 0;
  for (let i in input) {
    sum += input[i];
  }
return Math.floor((n * (n + 1)) / 2) - sum;
};
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Input: [1, 2, 3, 4, 6, 7, 8, 9, 10]
Output: 5

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2. Inverting integers in JavaScript

const reverse = function(num) {
    let result = 0;
    while (num !== 0) {
      result = result * 10 + num % 10;
      // Math.trunc() ๆ–นๆณ•ไผšๅฐ†ๆ•ฐๅญ—็š„ๅฐๆ•ฐ้ƒจๅˆ†ๅŽปๆŽ‰๏ผŒๅชไฟ็•™ๆ•ดๆ•ฐ้ƒจๅˆ†
      num = Math.trunc(num / 10);
    }
if (result > 2**31 || result < -(2**31)) return 0;
    return result;
};

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Input: num = 123
Output: 321
Input: num = -123
Output: -321
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3.Array alignment

const permute = function(nums) {
    let results = [];
let go = (current) => {
      if (current.length === nums.length){
        results.push(current);
        return;
      }
      nums.forEach(n => {
        if (!current.includes(n)){
          go([...current, n]);
        }
      });
    }
    go([]);
    return results;
};
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Input: [1,2,3]
Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
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4.Alignment in strings

const checkPermutation = function(s1, s2) {
  const len1 = s1.length, len2 = s2.length;
  if (len1 > len2) return false;
const count = Array(26).fill(0);
  for (let i = 0; i < len1; i++) {
      count[s1.charCodeAt(i)-97]++;
      count[s2.charCodeAt(i)-97]--;
  }
  if (!count.some(e => e !== 0)) return true;
for (let i = len1; i < len2; i++) {
      count[s2.charCodeAt(i)-97]--;
      count[s2.charCodeAt(i-len1)-97]++;
      if (!count.some(e => e !== 0)) return true;
  }
  return false;
};
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Input: s1 = โ€œabโ€, s2 = โ€œeidbaoโ€
Output: true
Input: s1 = โ€œaaโ€, s2 = โ€œeidbaoโ€
Output: false

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5.Longest valid brackets

const longestValidParentheses = function(S) {
  let stack = [-1], ans = 0;
  for (let i = 0; i < S.length; i++)
    if (S[i] === '(') stack.push(i)
    else if (stack.length === 1) stack[0] = i
    else stack.pop(), ans = Math.max(ans, i - stack[stack.length-1])
  return ans
};
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Input: โ€œ(()โ€
Output: 2
Input: โ€œ)()())โ€
Output: 4
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6.String multiplication

const multiply = function(num1, num2) {
 if (num1 == 0 || num2 == 0) return โ€˜0โ€™;
 const result = [];
for (let a = num1.length โ€” 1; a >= 0; a โ€” ) {
 for (let b = num2.length โ€” 1; b >= 0; b โ€” ) {
 const p1 = a + b;
 const p2 = a + b + 1;
 const sum = (result[p2] ?? 0) + num1[a] * num2[b];
result[p1] = (result[p1] ?? 0) + Math.floor(sum / 10);
 result[p2] = sum % 10;
 }
 }
 result[0] == 0 && result.shift();
 return result.join(โ€˜โ€™);
};
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Input: num1 = โ€œ2โ€, num2 = โ€œ3โ€
Output: โ€œ6โ€
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4Sum

const fourSum = function(nums, target) {
  let result = [];
  let length = nums.length;
  if (length < 4) return result; 
  nums = nums.sort((a, b) => a - b );
for (let i = 0; i < length - 3; i++) {
    if (nums[i] === nums[i - 1]) continue;
    for (let j = i + 1; j < length - 2; j++) {
      if (j > i + 1 && nums[j] === nums[j - 1]) continue;
let k = j + 1;
      let l = length - 1;
while (k < l) {
        const sum = nums[i] + nums[j] + nums[k] + nums[l];
if (sum === target) {
          result.push([nums[i], nums[j], nums[k], nums[l]])
        }
if (sum <= target) {
          k += 1;
          while (nums[k] === nums[k - 1]) {
            k += 1;
          }
        }
if (sum >= target) {
          l -= 1;
          while (nums[l] === nums[l + 1]) {
            l -= 1;
          }
        }
      }
    }
  }
return result;
};
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Akash Chauhan

The importance of gaming in Javascript is vast. It helps with hand-eye coordination, problem solving, and logic skills. Gaming can also relieve stress, improve moods, and promote social interaction.
Here find how you can improve your JavaScript skills with Javascript gaming

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