compare_version_numbers

Author: hitzzc

README.md

@@ -142,7 +142,7 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [160. Intersection of Two Linked Lists](https://github.com/hitzzc/go-leetcode/tree/master/intersection_of_two_linked_lists)
 #### [162. Find Peak Element](https://github.com/hitzzc/go-leetcode/tree/master/find_peak_element)
 #### [164. Maximum Gap](https://github.com/hitzzc/go-leetcode/tree/master/maximum_gap)
-
+#### [165. compare version numbers](https://github.com/hitzzc/go-leetcode/tree/master/compare_version_numbers)
 
 
 

compare_version_numbers/compare_version_numbers.go

@@ -0,0 +1,33 @@
+package compare_version_numbers
+
+func compareVersion(version1 string, version2 string) int {
+	bytes1, bytes2 := []byte(version1), []byte(version2)
+	bToI := map[byte]int{
+		'0': 0,
+		'1': 1,
+		'2': 2,
+		'3': 3,
+		'4': 4,
+		'5': 5,
+		'6': 6,
+		'7': 7,
+		'8': 8,
+		'9': 9,
+	}
+	i, j := -1, -1
+	for i < len(bytes1) || j < len(bytes2) {
+		var num1, num2 int
+		for i++; i < len(bytes1) && bytes1[i] != '.'; i++ {
+			num1 = num1*10 + bToI[bytes1[i]]
+		}
+		for j++; j < len(bytes2) && bytes2[j] != '.'; j++ {
+			num2 = num2*10 + bToI[bytes2[j]]
+		}
+		if num1 > num2 {
+			return 1
+		} else if num1 < num2 {
+			return -1
+		}
+	}
+	return 0
+}