missing_number

Author: hitzzc

README.md

@@ -203,6 +203,7 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [260. Single Number III](https://github.com/hitzzc/go-leetcode/tree/master/single_number_III)
 #### [263. Ugly Number](https://github.com/hitzzc/go-leetcode/tree/master/ugly_number)
 #### [264. Ugly Number II](https://github.com/hitzzc/go-leetcode/tree/master/ugly_number_II)
+#### [268. Missing Number](https://github.com/hitzzc/go-leetcode/tree/master/missing_number)
 
 
 

missing_number/missing_number.go

@@ -0,0 +1,17 @@
+package missing_number
+
+func missingNumber(nums []int) int {
+	ret := 0
+	for i := range nums {
+		ret ^= nums[i] ^ (i + 1)
+	}
+	return ret
+}
+
+func missingNumberI(nums []int) int {
+	ret := 0
+	for i := range nums {
+		ret += i + 1 - nums[i]
+	}
+	return ret
+}