Sri Hari: Batch-9/Added articles/Neetcode All (#4689)

* Batch-9/Neetcode-ALL/Added-articles

* Batch-9/Neetcode-ALL/Added-articles

* Batch-9/Neetcode-ALL/Added-articles

* Batch-9/Neetcode-ALL/Added-articles

* Batch-9/Neetcode-ALL/Added-articles

Author: Srihari2222

articles/arranging-coins.md

@@ -56,6 +56,19 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int ArrangeCoins(int n) {
+        int row = 0;
+        while (n - row > 0) {
+            row++;
+            n -= row;
+        }
+        return row;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -157,6 +170,29 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int ArrangeCoins(int n) {
+        int l = 1, r = n;
+        int res = 0;
+
+        while (l <= r) {
+            int mid = l + (r - l) / 2;
+            long coins = (long)mid * (mid + 1) / 2;
+
+            if (coins > n) {
+                r = mid - 1;
+            } else {
+                res = Math.Max(res, mid);
+                l = mid + 1;
+            }
+        }
+
+        return res;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -262,6 +298,30 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int ArrangeCoins(int n) {
+        if (n <= 3) {
+            return n == 1 ? 1 : n - 1;
+        }
+
+        int l = 1, r = (n / 2) + 1;
+        while (l < r) {
+            int mid = (l + r) / 2;
+            long coins = (long)mid * (mid + 1) / 2;
+
+            if (coins <= n) {
+                l = mid + 1;
+            } else {
+                r = mid;
+            }
+        }
+
+        return l - 1;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -348,6 +408,26 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int ArrangeCoins(int n) {
+        int mask = 1 << 15;
+        int rows = 0;
+
+        while (mask > 0) {
+            rows |= mask;
+            long coins = (long)rows * (rows + 1) / 2;
+            if (coins > n) {
+                rows ^= mask;
+            }
+            mask >>= 1;
+        }
+
+        return rows;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -396,6 +476,14 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int ArrangeCoins(int n) {
+        return (int)(Math.Sqrt(2L * n + 0.25) - 0.5);
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity

articles/buy-two-chocolates.md

@@ -48,6 +48,11 @@ public:
 
 ```javascript
 class Solution {
+    /**
+     * @param {number[]} prices
+     * @param {number} money
+     * @return {number}
+     */
     buyChoco(prices, money) {
         let res = -1;
         for (let i = 0; i < prices.length; i++) {
@@ -62,6 +67,22 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int BuyChoco(int[] prices, int money) {
+        int res = -1;
+        for (int i = 0; i < prices.Length; i++) {
+            for (int j = i + 1; j < prices.Length; j++) {
+                if (prices[i] + prices[j] <= money) {
+                    res = Math.Max(res, money - prices[i] - prices[j]);
+                }
+            }
+        }
+        return res == -1 ? money : res;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -106,6 +127,11 @@ public:
 
 ```javascript
 class Solution {
+    /**
+     * @param {number[]} prices
+     * @param {number} money
+     * @return {number}
+     */
     buyChoco(prices, money) {
         prices.sort((a, b) => a - b);
         let buy = prices[0] + prices[1];
@@ -114,6 +140,16 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int BuyChoco(int[] prices, int money) {
+        Array.Sort(prices);
+        int buy = prices[0] + prices[1];
+        return buy > money ? money : money - buy;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -185,6 +221,11 @@ public:
 
 ```javascript
 class Solution {
+    /**
+     * @param {number[]} prices
+     * @param {number} money
+     * @return {number}
+     */
     buyChoco(prices, money) {
         let min1 = Infinity,
             min2 = Infinity;
@@ -204,6 +245,26 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int BuyChoco(int[] prices, int money) {
+        int min1 = int.MaxValue, min2 = int.MaxValue;
+
+        foreach (int p in prices) {
+            if (p < min1) {
+                min2 = min1;
+                min1 = p;
+            } else if (p < min2) {
+                min2 = p;
+            }
+        }
+
+        int leftover = money - min1 - min2;
+        return leftover >= 0 ? leftover : money;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity

articles/count-odd-numbers-in-an-interval-range.md

@@ -60,6 +60,20 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int CountOdds(int low, int high) {
+        int odd = 0;
+        for (int num = low; num <= high; num++) {
+            if ((num & 1) == 1) {
+                odd++;
+            }
+        }
+        return odd;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -130,6 +144,19 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int CountOdds(int low, int high) {
+        int length = high - low + 1;
+        int count = length / 2;
+        if ((length % 2 == 1) && (low % 2 == 1)) {
+            count++;
+        }
+        return count;
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity
@@ -179,6 +206,14 @@ class Solution {
 }
 ```
 
+```csharp
+public class Solution {
+    public int CountOdds(int low, int high) {
+        return ((high + 1) >> 1) - (low >> 1);
+    }
+}
+```
+
 ::tabs-end
 
 ### Time & Space Complexity