feat: add python and java solutions to leetcode problem: No.0441

Author: yanglbme

solution/0400-0499/0441.Arranging Coins/README.md

@@ -42,22 +42,34 @@ n = 8
 
 <!-- 这里可写通用的实现逻辑 -->
 
+`(1 + x) * x / 2 <= n`，求解 x。
+
+`(x + 1/2)² <= 2n + 1/4`，即 `x <= sqrt(2n + 1/4) - 1/2`。
+
+由于 2n 可能溢出，故转换为 `x <= sqrt(2) * sqrt(n + 1/8) - 1/2`。
+
 <!-- tabs:start -->
 
 ### **Python3**
 
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```python
-
+class Solution:
+    def arrangeCoins(self, n: int) -> int:
+        return int(math.sqrt(2) * math.sqrt(n + 0.125) - 0.5)
 ```
 
 ### **Java**
 
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
-
+class Solution {
+    public int arrangeCoins(int n) {
+        return (int) (Math.sqrt(2) * Math.sqrt(n + 0.125) - 0.5);
+    }
+}
 ```
 
 ### **...**

solution/0400-0499/0441.Arranging Coins/README_EN.md

@@ -67,13 +67,19 @@ Because the 4th row is incomplete, we return 3.
 ### **Python3**
 
 ```python
-
+class Solution:
+    def arrangeCoins(self, n: int) -> int:
+        return int(math.sqrt(2) * math.sqrt(n + 0.125) - 0.5)
 ```
 
 ### **Java**
 
 ```java
-
+class Solution {
+    public int arrangeCoins(int n) {
+        return (int) (Math.sqrt(2) * Math.sqrt(n + 0.125) - 0.5);
+    }
+}
 ```
 
 ### **...**

solution/0400-0499/0441.Arranging Coins/Solution.java

@@ -1,11 +1,5 @@
 class Solution {
     public int arrangeCoins(int n) {
-        int l = 0, r = n;
-        while (l < r) {
-            int mid = l + r + 1 >>> 1;
-            if (1L * mid * (mid + 1) / 2 <= n) l = mid;
-            else r = mid - 1;
-        }
-        return r;
+        return (int) (Math.sqrt(2) * Math.sqrt(n + 0.125) - 0.5);
     }
-}
+}

solution/0400-0499/0441.Arranging Coins/Solution.py

@@ -0,0 +1,3 @@
+class Solution:
+    def arrangeCoins(self, n: int) -> int:
+        return int(math.sqrt(2) * math.sqrt(n + 0.125) - 0.5)