feat: update solutions to lcof problems

更新剑指Offer题解

Author: yanglbme

lcof/面试题14- I. 剪绳子/README.md

@@ -26,6 +26,8 @@
 
 ## 解法
 
+尽可能将绳子以长度 3 等分剪为多段时，乘积最大。
+
 <!-- tabs:start -->
 
 ### **Python3**
@@ -35,28 +37,28 @@ class Solution:
     def cuttingRope(self, n: int) -> int:
         if n < 4:
             return n - 1
-        s1, m = divmod(n, 3)
-        if m == 1:
-            s1 -= 1
-            m = 4
-        return pow(3, s1) * (1 if m == 0 else m)
+        res = 1
+        while n > 4:
+            res *= 3
+            n -= 3
+        if n == 4:
+            return res << 2
+        return res * n
 ```
 
 ### **Java**
 
 ```java
 class Solution {
     public int cuttingRope(int n) {
-        if (n < 4) {
-            return n - 1;
-        }
-        int s1 = n / 3;
-        int m = n % 3;
-        if (m == 1) {
-            s1 -= 1;
-            m = 4;
+        if (n < 4) return n - 1;
+        int res = 1;
+        while (n > 4) {
+            res *= 3;
+            n -= 3;
         }
-        return (int) (Math.pow(3, s1) * ((m == 0) ? 1 : m));
+        if (n == 4) return res << 2;
+        return res * n;
     }
 }
 ```

lcof/面试题14- I. 剪绳子/Solution.java

@@ -1,14 +1,12 @@
 class Solution {
     public int cuttingRope(int n) {
-        if (n < 4) {
-            return n - 1;
+        if (n < 4) return n - 1;
+        int res = 1;
+        while (n > 4) {
+            res *= 3;
+            n -= 3;
         }
-        int s1 = n / 3;
-        int m = n % 3;
-        if (m == 1) {
-            s1 -= 1;
-            m = 4;
-        }
-        return (int) (Math.pow(3, s1) * ((m == 0) ? 1 : m));
+        if (n == 4) return res << 2;
+        return res * n;
     }
 }

lcof/面试题14- I. 剪绳子/Solution.py

@@ -2,8 +2,10 @@ class Solution:
     def cuttingRope(self, n: int) -> int:
         if n < 4:
             return n - 1
-        s1, m = divmod(n, 3)
-        if m == 1:
-            s1 -= 1
-            m = 4
-        return pow(3, s1) * (1 if m == 0 else m)
+        res = 1
+        while n > 4:
+            res *= 3
+            n -= 3
+        if n == 4:
+            return res << 2
+        return res * n

lcof/面试题14- II. 剪绳子 II/README.md

@@ -37,11 +37,13 @@ class Solution:
     def cuttingRope(self, n: int) -> int:
         if n < 4:
             return n - 1
-        s1, m = divmod(n, 3)
-        if m == 1:
-            s1 -= 1
-            m = 4
-        return (pow(3, s1) * (1 if m == 0 else m)) % 1000000007
+        res = 1
+        while n > 4:
+            res *= 3
+            n -= 3
+        if n == 4:
+            return (res << 2) % 1000000007
+        return (res * n) % 1000000007
 ```
 
 ### **Java**

lcof/面试题14- II. 剪绳子 II/Solution.py

@@ -2,8 +2,10 @@ class Solution:
     def cuttingRope(self, n: int) -> int:
         if n < 4:
             return n - 1
-        s1, m = divmod(n, 3)
-        if m == 1:
-            s1 -= 1
-            m = 4
-        return (pow(3, s1) * (1 if m == 0 else m)) % 1000000007
+        res = 1
+        while n > 4:
+            res *= 3
+            n -= 3
+        if n == 4:
+            return (res << 2) % 1000000007
+        return (res * n) % 1000000007