feat: add golang solution for lcof problem 14II 15 16

Author: hzliangbin

lcof/面试题14- II. 剪绳子 II/README.md

@@ -88,7 +88,27 @@ var cuttingRope = function(n) {
 };
 ```
 
+### Go
+
+```go
+func cuttingRope(n int) int {
+    if n <= 3 {
+        return n-1
+    }
+    sum := 1
+    for n > 4 {
+        sum *=  3
+        sum = sum%1000000007 
+        n -= 3
+    }
+    return sum*n%1000000007
+}
+```
+
+
+
 ### ...
+
 ```
 
 ```

lcof/面试题14- II. 剪绳子 II/Solution.go

@@ -0,0 +1,12 @@
+func cuttingRope(n int) int {
+    if n <= 3 {
+        return n-1
+    }
+    sum := 1
+    for n > 4 {
+        sum *=  3
+        sum = sum%1000000007 
+        n -= 3
+    }
+    return sum*n%1000000007
+}

lcof/面试题15. 二进制中1的个数/README.md

@@ -72,7 +72,24 @@ var hammingWeight = function(n) {
 };
 ```
 
+### Go
+
+```go
+func hammingWeight(num uint32) int {
+    ans := 0 
+    // num &=num-1 消除最右边的1
+    for num != 0 {
+        num &=num-1
+        ans++
+    }
+    return ans
+}
+```
+
+
+
 ### ...
+
 ```
 
 ```

lcof/面试题15. 二进制中1的个数/Solution.go

@@ -0,0 +1,9 @@
+func hammingWeight(num uint32) int {
+    ans := 0 
+    // num &=num-1 消除最右边的1
+    for num != 0 {
+        num &=num-1
+        ans++
+    }
+    return ans
+}

lcof/面试题16. 数值的整数次方/README.md

@@ -90,7 +90,38 @@ var myPow = function(x, n) {
 };
 ```
 
+### Go
+
+```go
+func myPow(x float64, n int) float64 {
+    p := abs(n)
+    res := 1.0
+    for p != 0 {
+        if p&1 == 1 {
+            res *= x
+        } 
+        x *= x
+        p = p >>1 
+    }
+    if n < 0 {
+        return 1/res
+    }
+    return res
+}
+
+func abs(x int) int {
+    if x > 0 {
+        return x
+    }
+    return -x
+}
+
+```
+
+
+
 ### ...
+
 ```
 
 ```

lcof/面试题16. 数值的整数次方/Solution.go

@@ -0,0 +1,23 @@
+func myPow(x float64, n int) float64 {
+    p := abs(n)
+    res := 1.0
+    for p != 0 {
+        if p&1 == 1 {
+            res *= x
+        } 
+        x *= x
+        p = p >>1 
+    }
+    if n < 0 {
+        return 1/res
+    }
+    return res
+}
+
+func abs(x int) int {
+    if x > 0 {
+        return x
+    }
+    return -x
+}
+