Add power-of-four.go

Author: tinycedar

power-of-four.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"fmt"
+)
+
+func isPowerOfFour(num int) bool {
+	if num <= 0 {
+		return false
+	}
+	for ; num%4 == 0; num /= 4 {
+	}
+	return num == 1
+}
+
+func main() {
+	fmt.Println(isPowerOfFour(8))
+}