palindrome_number

Author: hitzzc

README.md

@@ -10,5 +10,6 @@ leetcode for golang
 #### [6. zigzag conversion](https://github.com/hitzzc/go-leetcode/tree/master/zigzag_conversion)
 #### [7. reverse integer](https://github.com/hitzzc/go-leetcode/tree/master/reverse_integer)
 #### [8. string to integer](https://github.com/hitzzc/go-leetcode/tree/master/string_to_integer)
+#### [9. palindrome number](https://github.com/hitzzc/go-leetcode/tree/master/palindrome_number)
 
 

palindrome_number/palindrome_number.go

@@ -0,0 +1,34 @@
+package palindrome_number
+
+func isPalindrome(x int) bool {
+	if x < 0 {
+		return false
+	}
+	bits := 1
+	tmp := x
+	for {
+		if tmp < 10 {
+			break
+		}
+		tmp = tmp / 10
+		bits++
+	}
+	i, j := 1, bits
+	for i < j {
+		left := (x / divisor(i)) % 10
+		right := (x / divisor(j)) % 10
+		if left != right {
+			return false
+		}
+		i, j = i+1, j-1
+	}
+	return true
+}
+
+func divisor(bits int) int {
+	ret := 1
+	for i := 0; i < bits-1; i++ {
+		ret = ret * 10
+	}
+	return ret
+}

palindrome_number/palindrome_number_test.go

@@ -0,0 +1,9 @@
+package palindrome_number
+
+import (
+	"testing"
+)
+
+func TestIsPalindrome(t *testing.T) {
+
+}