diff --git a/Challenge-1/two-sum.js b/Challenge-1/two-sum.js
new file mode 100644
index 0000000..ff191e2
--- /dev/null
+++ b/Challenge-1/two-sum.js
@@ -0,0 +1,15 @@
+var twoSum = function (nums, target) {
+    let obj = {}
+    for (i = 0; i < nums.length; i++) {
+        let diff = target - nums[i]
+        if (obj[diff] != null) {
+            return [obj[diff], i]
+        } else {
+            obj[nums[i]] = i
+            console.log(obj)
+        }
+    }
+};
+const nums = [2, 7, 11, 15];
+const target = 9;
+console.log(twoSum(nums, target));
\ No newline at end of file
diff --git a/Challenge-10/Search in Rotated Sorted Array.js b/Challenge-10/Search in Rotated Sorted Array.js
new file mode 100644
index 0000000..38b71d4
--- /dev/null
+++ b/Challenge-10/Search in Rotated Sorted Array.js	
@@ -0,0 +1,47 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+
+function getPivot(arr) {
+    var s = 0, e = arr.length - 1;
+    while (s < e) {
+        var mid = Math.floor(s + (e - s) / 2)
+
+        if (arr[mid] >= arr[0]) {
+            s = mid + 1
+        } else {
+            e = mid
+        }
+    }
+    return s;
+}
+
+function binarySearch(arr, start, end, key) {
+    var s = start, e = end;
+
+    while (s <= e) {
+        var mid = Math.floor(s + (e - s) / 2)
+        if (arr[mid] == key) {
+            return mid
+        }
+        if (key > arr[mid]) {
+            s = mid + 1;
+        } else {
+            e = mid - 1
+        }
+    }
+    return -1;
+}
+var search = function (arr, target) {
+    var n = arr.length
+    var pivot = getPivot(arr)
+
+    if (target >= arr[pivot] && target <= arr[n - 1]) {
+        return binarySearch(arr, pivot, n - 1, target)
+    } else {
+        return binarySearch(arr, 0, pivot - 1, target)
+    }
+
+};
\ No newline at end of file
diff --git a/Challenge-11/3sum.js b/Challenge-11/3sum.js
new file mode 100644
index 0000000..5408783
--- /dev/null
+++ b/Challenge-11/3sum.js
@@ -0,0 +1,37 @@
+/**
+ * @param {number[]} nums
+ * @return {number[][]}
+ */
+var threeSum = function (nums) {
+    let n = nums.length;
+    const ans = [];
+
+    nums.sort((a, b) => a - b);
+
+    for (let i = 0; i < n - 2; i++) {
+        if (i > 0 && nums[i] === nums[i - 1]) continue;
+
+        let j = i + 1, k = n - 1;
+
+        while (j < k) {
+            let sum = nums[i] + nums[j] + nums[k];
+
+            if (sum < 0) {
+                j++;
+            } else if (sum > 0) {
+                k--;
+            } else {
+                ans.push([nums[i], nums[j], nums[k]]);
+                // Skip duplicate values for 'j'
+                while (j < k && nums[j] === nums[j + 1]) j++;
+                // Skip duplicate values for 'k'
+                while (j < k && nums[k] === nums[k - 1]) k--;
+
+                j++;
+                k--;
+            }
+        }
+    }
+
+    return ans;
+};
\ No newline at end of file
diff --git a/Challenge-12/Container With Most Water.js b/Challenge-12/Container With Most Water.js
new file mode 100644
index 0000000..c128357
--- /dev/null
+++ b/Challenge-12/Container With Most Water.js	
@@ -0,0 +1,23 @@
+/**
+ * @param {number[]} height
+ * @return {number}
+ * https://leetcode.com/problems/container-with-most-water/
+ */
+
+var maxArea = function (h) {
+    let left = 0
+    let right = h.length - 1
+    let maxWater = 0
+    while (left < right) {
+        let minH = Math.min(h[left], h[right])
+        maxWater = Math.max(maxWater, minH * (right - left))
+        if (h[left] < h[right]) left++
+        else right--
+
+    }
+
+
+
+
+    return maxWater
+};
diff --git a/Challenge-13/Number of 1 Bits.js b/Challenge-13/Number of 1 Bits.js
new file mode 100644
index 0000000..11e8903
--- /dev/null
+++ b/Challenge-13/Number of 1 Bits.js	
@@ -0,0 +1,17 @@
+/**
+ * @param {number[]} height
+ * @return {number}
+ * https://leetcode.com/problems/number-of-1-bits/
+ */
+
+var hammingWeight = function (n) {
+    var count = 0;
+    while (n != 0) {
+        if (n & 1) {
+            count++;
+        }
+        n = n >> 1;
+    }
+    return count;
+
+};
diff --git a/Challenge-14/Counting Bits.js b/Challenge-14/Counting Bits.js
new file mode 100644
index 0000000..0e28b9c
--- /dev/null
+++ b/Challenge-14/Counting Bits.js	
@@ -0,0 +1,18 @@
+/**
+ * @param {number} n
+ * @return {number[]}
+ * https://leetcode.com/problems/counting-bits/
+ */
+var countBits = function (n) {
+    const ans = []
+    for (var i = 0; i <= n; i++) {
+        const binary = i.toString(2);
+        let count = 0
+        console.log("binary", binary)
+        for (let i = 0; i < binary.length; i++) {
+            if (binary[i] === '1') count++;
+        }
+        ans.push(count)
+    }
+    return ans
+};
\ No newline at end of file
diff --git a/Challenge-15/Missing Number.js b/Challenge-15/Missing Number.js
new file mode 100644
index 0000000..bfefc88
--- /dev/null
+++ b/Challenge-15/Missing Number.js	
@@ -0,0 +1,11 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var missingNumber = function (nums) {
+    let n = nums.length;
+    let expectedSum = (n * (n + 1)) / 2;
+    let actualSum = nums.reduce((acc, num) => acc + num, 0);
+    return expectedSum - actualSum;
+
+};
\ No newline at end of file
diff --git a/Challenge-16/Reverse Bits.js b/Challenge-16/Reverse Bits.js
new file mode 100644
index 0000000..f64e68a
--- /dev/null
+++ b/Challenge-16/Reverse Bits.js	
@@ -0,0 +1,14 @@
+/**
+ * @param {number} n - a positive integer
+ * @return {number} - a positive integer
+ * https://leetcode.com/problems/reverse-bits/
+ */
+
+var reverseBits = function (n) {
+    let result = n.toString(2)
+    result = result.padStart(32, '0');
+    let reversedString = result.split('').reverse().join('');
+    let ans = parseInt(reversedString, 2)
+    return ans
+};
+console.log(reverseBits(43261596)) // 964176192
\ No newline at end of file
diff --git a/Challenge-17/Climbing Stairs.js b/Challenge-17/Climbing Stairs.js
new file mode 100644
index 0000000..a7da067
--- /dev/null
+++ b/Challenge-17/Climbing Stairs.js	
@@ -0,0 +1,27 @@
+/**
+ * @param {number} n
+ * @return {number}
+ * https://leetcode.com/problems/climbing-stairs/submissions/713423865/
+ */
+function numberOfWays(n, memo) {
+    if (n == 0)
+        return 1;
+    if (n < 0) {
+        return 0
+    };
+    if (n == 1)
+        return 1
+
+    if (memo[n] != -1)
+        return memo[n]
+
+    return memo[n] = numberOfWays(n - 1, memo) + numberOfWays(n - 2, memo)
+}
+var climbStairs = function (n) {
+    var cur = 0
+    var memo = new Array(n + 1).fill(-1)
+    var ans = numberOfWays(n, memo)
+
+
+    return ans
+};
\ No newline at end of file
diff --git a/Challenge-18/Coin Change.js b/Challenge-18/Coin Change.js
new file mode 100644
index 0000000..b19339b
--- /dev/null
+++ b/Challenge-18/Coin Change.js	
@@ -0,0 +1,33 @@
+/**
+ * @param {number[]} coins
+ * @param {number} amount
+ * @return {number}
+ * https://leetcode.com/problems/coin-change/description/
+ */
+function ANS(arr, index, T, dp) {
+
+    if (index == 0) {
+        if (T % arr[0] == 0) return T / arr[0];
+        else return 1e9;
+    }
+    if (dp[index][T] !== -1) return dp[index][T]
+    var notTaken = 0 + ANS(arr, index - 1, T, dp)
+
+    var taken = 1e9;
+    if (arr[index] <= T)
+        taken = 1 + ANS(arr, index, T - arr[index], dp);
+
+    return dp[index][T] = Math.min(notTaken, taken);
+}
+var coinChange = function (arr, target) {
+    var n = arr.length
+    var dp = []
+    for (var i = 0; i <= n; i++) {
+        dp[i] = new Array(target + 1).fill(-1)
+    }
+
+    var ans = ANS(arr, n - 1, target, dp)
+    if (ans >= 1e9) return -1;
+    return ans
+
+};
\ No newline at end of file
diff --git a/Challenge-2/best-time-to-buy-and-sell-stock.js b/Challenge-2/best-time-to-buy-and-sell-stock.js
new file mode 100644
index 0000000..d2c1390
--- /dev/null
+++ b/Challenge-2/best-time-to-buy-and-sell-stock.js
@@ -0,0 +1,11 @@
+function maxProfit(prices) {
+    let minPrice = Infinity;
+    let maxProfit = 0;
+
+    for (let price of prices) {
+        minPrice = Math.min(minPrice, price);
+        maxProfit = Math.max(maxProfit, price - minPrice);
+    }
+
+    return maxProfit;
+}
diff --git a/Challenge-3/contain-duplicate.js b/Challenge-3/contain-duplicate.js
new file mode 100644
index 0000000..bdb4543
--- /dev/null
+++ b/Challenge-3/contain-duplicate.js
@@ -0,0 +1,13 @@
+var containsDuplicate = function (nums) {
+    const obj = {}
+    for (let i = 0; i < nums.length; i++) {
+        if (obj[nums[i]]) {
+            return true
+        }
+        obj[nums[i]] = true
+    }
+
+    return false
+
+};
+containsDuplicate([1, 2, 3, 1]); 
\ No newline at end of file
diff --git a/Challenge-4/Sum-of-Two-Integers.js b/Challenge-4/Sum-of-Two-Integers.js
new file mode 100644
index 0000000..f1bf196
--- /dev/null
+++ b/Challenge-4/Sum-of-Two-Integers.js
@@ -0,0 +1,9 @@
+var getSum = function (a, b) {
+    while (b !== 0) {
+        let carry = (a & b) << 1;
+        a = a ^ b;
+        b = carry;
+    }
+    return a;
+};
+getSum(1, 2);
\ No newline at end of file
diff --git a/Challenge-5/Product of Array Except Self.js b/Challenge-5/Product of Array Except Self.js
new file mode 100644
index 0000000..a8339e9
--- /dev/null
+++ b/Challenge-5/Product of Array Except Self.js	
@@ -0,0 +1,31 @@
+var productExceptSelf = function (nums) {
+    const arr = []
+    const prefixArr = []
+    const suffixArr = []
+    for (let i = 0; i < nums.length; i++) {
+        if (i === 0) {
+            prefixArr[i] = 1
+
+
+        } else {
+            prefixArr[i] = prefixArr[i - 1] * nums[i - 1]
+        }
+
+    }
+    for (var i = nums.length - 1; i >= 0; i--) {
+        if (i === nums.length - 1) {
+            suffixArr[i] = 1
+        } else {
+            suffixArr[i] = suffixArr[i + 1] * nums[i + 1]
+        }
+    }
+    for (let i = 0; i < nums.length; i++) {
+        arr[i] = prefixArr[i] * suffixArr[i]
+
+
+    };
+    return arr
+}
+
+console.log(productExceptSelf([1, 2, 3, 4])); 
+
diff --git a/Challenge-8/Product-sub-array.js b/Challenge-8/Product-sub-array.js
new file mode 100644
index 0000000..2cf2dac
--- /dev/null
+++ b/Challenge-8/Product-sub-array.js
@@ -0,0 +1,12 @@
+var maxProduct = function (arr) {
+    let res = arr[0];
+    let currMin = 1
+    let currMax = 1
+    for (var i = 0; i < arr.length; i++) {
+        let temp = currMax
+        currMax = Math.max(arr[i], arr[i] * currMax, arr[i] * currMin)
+        currMin = Math.min(arr[i], arr[i] * temp, arr[i] * currMin)
+        res = Math.max(res, currMax)
+    }
+    return res
+};
\ No newline at end of file
diff --git a/Challenge-9/Find Minimum in Rotated Sorted Array.js b/Challenge-9/Find Minimum in Rotated Sorted Array.js
new file mode 100644
index 0000000..1a517b1
--- /dev/null
+++ b/Challenge-9/Find Minimum in Rotated Sorted Array.js	
@@ -0,0 +1,20 @@
+var findMin = function (nums) {
+    var s = 0, e = nums.length - 1;
+    var res = nums[0];
+
+    while (s <= e) {
+        if (nums[s] < nums[e]) {
+            res = nums[s];
+            break
+        }
+        var mid = Math.floor((s + e) / 2);
+        res = Math.min(res, nums[mid]);
+        if (nums[s] <= nums[mid]) { //left sort
+            s = mid + 1; //got to right
+        } else {
+            e = mid;
+        }
+    }
+    return res ;
+
+};
\ No newline at end of file
diff --git a/README.md b/README.md
index d922b9d..6eac5ef 100644
--- a/README.md
+++ b/README.md
@@ -1,148 +1,2 @@
-# GitHub Guide for Submitting Challenge Solutions
-
-Welcome to the GitHub repository for coding challenges! This guide will walk you through the process of creating a branch under your name and uploading your solution files step by step. If you are new to Git and GitHub, follow these instructions carefully.
-
----
-
-## 🚀 Setting Up Git and GitHub
-
-### 1️⃣ Install Git
-If you haven't installed Git yet, download and install it from [Git's official website](https://git-scm.com/downloads).
-
-### 2️⃣ Create a GitHub Account
-If you don’t have a GitHub account, create one at [GitHub](https://github.com/).
-
-### 3️⃣ Fork the Repository
-1. Go to the repository URL shared by your instructor.
-2. Click on the **Fork** button in the top-right corner to create a copy in your GitHub account.
-
-### 4️⃣ Clone the Repository Locally
-1. Open **Terminal** (Linux/macOS) or **Command Prompt/Powershell** (Windows).
-2. Run the following command, replacing `your-username` with your GitHub username:
-   
-   ```sh
-   git clone https://github.com/WeCode-Community-Dev/blind-75-challenge.git
-   ```
-   
-3. Navigate into the repository folder:
-   
-   ```sh
-   cd blind-75-challenge
-   ```
-
----
-
-## 🌿 Creating a Branch Under Your Name
-Each student must create a separate branch with their name before making any changes.
-
-1. Check the current branches:
-   
-   ```sh
-   git branch
-   ```
-   
-2. Create a new branch with your name (make sure this is unique - add some unique number or characters to make sure it is not already there):
-   
-   ```sh
-   git checkout -b your-branch-name
-   ```
-   
-3. Verify the branch was created and switched to it:
-   
-   ```sh
-   git branch
-   ```
-   
-   Your name should now be highlighted, meaning you are on that branch.
-
----
-
-## 🔁 Setting Upstream and Pulling Latest Changes
-Before working on a new challenge, ensure your repository is up to date.
-
-1. Add the original repository as the upstream remote (only required once):
-   
-   ```sh
-   git remote add upstream https://github.com/WeCode-Community-Dev/blind-75-challenge.git
-   ```
-   
-2. Fetch the latest changes:
-   
-   ```sh
-   git fetch upstream
-   ```
-   
-3. Merge the latest changes into your branch:
-   
-   ```sh
-   git merge upstream/main
-   ```
-
----
-
-## ✏️ Adding Your Challenge Solution
-Upload only the solution file for each challenge (e.g., `solution.py`, `solution.cpp`, `solution.java`).
-you can name the file <problem-name>.py or <problem-name>.cpp or <problem-name>.java etc. 
-example: two-sum.py or two-sum.cpp or two-sum.java as per the programming language you choose
-
-1. Navigate to the folder for the challenge you are working on.
-2. Place your solution file inside the appropriate challenge folder.
-
-Example structure:
-
-```
-repository-name/
-│-- Challenge-1/
-│   │-- solution.py  # Your file
-│-- Challenge-2/
-│   │-- solution.cpp  # Another file
-```
-
----
-
-## 📤 Committing and Pushing Your Code
-
-Replace the "challenge-1" with problem name
-
-1. Add the file you modified:
-   
-   ```sh
-   git add Challenge-1/solution.py
-   ```
-   
-2. Commit your changes with a meaningful message:
-   
-   ```sh
-   git commit -m "Added solution for Challenge 1"
-   ```
-   
-3. Push your branch to your GitHub repository:
-   
-   ```sh
-   git push origin your-branch-name
-   ```
-
----
-
-## 🔄 Creating a Pull Request (Not Required)
-Once you've pushed your changes, you need to create a **Pull Request (PR)**.
-
-1. Go to your GitHub repository.
-2. Switch to your branch (`your-branch-name`).
-3. Click on **Compare & pull request**.
-4. Add a meaningful **title** and **description**.
-5. Click **Create pull request**.
-
-Your code will now be reviewed and merged by the instructor! 🎉
-
----
-
-## ❗ Important Rules
-✅ Always create a branch under your name.
-✅ Upload only the solution file (no unnecessary files or folders).
-✅ Keep your repository updated by pulling the latest changes.
-✅ Use meaningful commit messages.
-✅ Create a pull request for every challenge.
-
-Happy coding! 🚀
-
+name : Prathyu Prasad
+emial : prathyuprasad116@gmail.com
\ No newline at end of file