added today practice

Author: ashish8513

AddTwoPromise.js

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+// Given two promises promise1 and promise2, return a new promise. promise1 and promise2 will both resolve with a number. The returned promise should resolve with the sum of the two numbers.
+
+// promise1 = new Promise(resolve => setTimeout(() => resolve(2), 20)), 
+// promise2 = new Promise(resolve => setTimeout(() => resolve(5), 60))
+// Output: 7
+// Explanation: The two input promises resolve with the values of 2 and 5 respectively. The returned promise should resolve with a value of 2 + 5 = 7. The time the returned promise resolves is not judged for this problem.
+
+/**
+ * @param {Promise} promise1
+ * @param {Promise} promise2
+ * @return {Promise}
+ */
+var addTwoPromises = async function (promise1, promise2) {
+    let sum = await Promise.all([promise1, promise2]).then(([num1, num2]) => num1 + num2);
+    return sum;
+
+
+};
+
+// Both are same only logic has been different 
+
+var addTwoPromises = async function (promise1, promise2) {
+    const val1 = await promise1
+    const val2 = await promise2
+
+    return val1 + val2
+};

AllowOneFunctionCall.js

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+// Given a function fn, return a new function that is identical to the original function except that it ensures fn is called at most once.
+
+// The first time the returned function is called, it should return the same result as fn.
+// Every subsequent time it is called, it should return undefined.
+
+/**
+ * @param {Function} fn
+ * @return {Function}
+ */
+var once = function(fn) {
+    let flag=false;
+    return function(...args){
+        if(flag===false){
+            flag=true
+            return fn(...args)
+        }else{
+            return undefined
+        }
+    }
+};

Memoize.js

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+// Given a function fn, return a memoized version of that function.
+
+// A memoized function is a function that will never be called twice with the same inputs. Instead it will return a cached value.
+
+// You can assume there are 3 possible input functions: sum, fib, and factorial.
+
+// sum accepts two integers a and b and returns a + b. Assume that if a value has already been cached for the arguments (b, a) where a != b, it cannot be used for the arguments (a, b). For example, if the arguments are (3, 2) and (2, 3), two separate calls should be made.
+// fib accepts a single integer n and returns 1 if n <= 1 or fib(n - 1) + fib(n - 2) otherwise.
+// factorial accepts a single integer n and returns 1 if n <= 1 or factorial(n - 1) * n otherwise
+
+
+function memoized(fn) {
+    const cachedVal = {}
+    return function (...args) {
+        const val = args
+        if (val in cachedVal) {
+            return cachedVal[val]
+        }
+        else {
+            const result = fn(...args)
+            cachedVal[val] = result
+            return result
+        }
+    }
+}

README.md

@@ -1,50 +1,71 @@
-<p align="center"><h1 font="10rem" align="center">30 Days JavaScript Challenge</h1>
-Welcome to the 30 Days JavaScript Challenge! This repository is designed to help you improve your JavaScript skills through daily coding exercises. Each day, you'll tackle a new challenge to enhance your understanding of core JavaScript concepts.
-
-![First loading Page](https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/1day.png)
-
-Challenge Overview
-Day 1: Basic Syntax
-Task: Write a function to print "Hello, World!" to the console.
-Objective: Understand basic syntax and function creation.
-Day 2: Variables and Data Types
-Task: Create a program that declares different types of variables and prints them.
-Objective: Learn about data types and variable declaration.
-Day 3: Conditional Statements
-Task: Implement a function that checks if a number is positive, negative, or zero.
-Objective: Practice using if-else statements.
-Day 4: Loops
-Task: Write a function that prints numbers 1 to 10 using a loop.
-Objective: Understand for and while loops.
-Day 5: Functions
-Task: Create a function that calculates the factorial of a number.
-Objective: Learn function definition and recursion.
-Day 6: Arrays
-Task: Write a program that finds the largest number in an array.
-Objective: Practice working with arrays and array methods.
-Day 7: Objects
-Task: Create an object representing a person and print its properties.
-Objective: Understand object creation and property access.
-Day 8: String Manipulation
-Task: Implement a function that reverses a string.
-Objective: Learn string methods and manipulation.
-Day 9: DOM Manipulation
-Task: Write a script that changes the background color of a webpage when a button is clicked.
-Objective: Practice manipulating the DOM with JavaScript.
-Day 10: Event Handling
-Task: Create a form that validates user input and displays a message when submitted.
-Objective: Understand event handling and form validation.
-Day 11-30: [Continue with more advanced topics like Promises, Async/Await, APIs, Error Handling, etc.]
-
-
-![First loading Page](https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/leetcode.png)
-
-Consistency: Try to complete each day's challenge on the assigned day.
-Practice: Don't hesitate to revisit challenges or seek additional resources if needed.
-Collaboration: Engage with the community for support and feedback.
-
-![First loading Page](https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/vs.png)
-
-
-For Any Query Please contact me [email protected]
+<p align="center">
+  <img src="https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/1day.png" alt="Challenge Overview" width="600"/>
 </p>
+
+<h1 align="center" style="font-size: 3rem;">30 Days JavaScript Challenge</h1>
+
+<p align="center">
+  Welcome to the 30 Days JavaScript Challenge! This repository is designed to help you improve your JavaScript skills through daily coding exercises. Each day, you'll tackle a new challenge to enhance your understanding of core JavaScript concepts.
+</p>
+
+## Challenge Overview
+
+**Day 1: Basic Syntax**  
+- **Task**: Write a function to print "Hello, World!" to the console.  
+- **Objective**: Understand basic syntax and function creation.
+
+**Day 2: Variables and Data Types**  
+- **Task**: Create a program that declares different types of variables and prints them.  
+- **Objective**: Learn about data types and variable declaration.
+
+**Day 3: Conditional Statements**  
+- **Task**: Implement a function that checks if a number is positive, negative, or zero.  
+- **Objective**: Practice using if-else statements.
+
+**Day 4: Loops**  
+- **Task**: Write a function that prints numbers 1 to 10 using a loop.  
+- **Objective**: Understand for and while loops.
+
+**Day 5: Functions**  
+- **Task**: Create a function that calculates the factorial of a number.  
+- **Objective**: Learn function definition and recursion.
+
+**Day 6: Arrays**  
+- **Task**: Write a program that finds the largest number in an array.  
+- **Objective**: Practice working with arrays and array methods.
+
+**Day 7: Objects**  
+- **Task**: Create an object representing a person and print its properties.  
+- **Objective**: Understand object creation and property access.
+
+**Day 8: String Manipulation**  
+- **Task**: Implement a function that reverses a string.  
+- **Objective**: Learn string methods and manipulation.
+
+**Day 9: DOM Manipulation**  
+- **Task**: Write a script that changes the background color of a webpage when a button is clicked.  
+- **Objective**: Practice manipulating the DOM with JavaScript.
+
+**Day 10: Event Handling**  
+- **Task**: Create a form that validates user input and displays a message when submitted.  
+- **Objective**: Understand event handling and form validation.
+
+**Day 11-30**: [Continue with more advanced topics like Promises, Async/Await, APIs, Error Handling, etc.]
+
+<p align="center">
+  <img src="https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/leetcode.png" alt="LeetCode" width="600"/>
+</p>
+
+## Tips for Success
+
+- **Consistency**: Try to complete each day's challenge on the assigned day.
+- **Practice**: Don't hesitate to revisit challenges or seek additional resources if needed.
+- **Collaboration**: Engage with the community for support and feedback.
+
+<p align="center">
+  <img src="https://github.com/ashish8513/30-days-javascript-leetCode-challenges/blob/main/vs.png" alt="Visual Studio" width="600"/>
+</p>
+
+## Contact
+
+For any queries, please contact me at [[email protected]](mailto:[email protected])

Sleep.js

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+// Given a positive integer millis, write an asynchronous function that sleeps for millis milliseconds. It can resolve any value.
+