id 1397550358 Time: 5 ms MemUsage: 2.2 MB

leetcode/single-number/solution_1397550358.rs

@@ -0,0 +1,13 @@
+use std::collections::HashSet;
+
+impl Solution {
+    pub fn single_number(nums: Vec<i32>) -> i32 {
+        nums.iter().fold(HashSet::new(), |mut counter, x| {
+            match counter.get(x) {
+                None => counter.insert(*x),
+                Some(_) => counter.remove(x)
+            };
+            counter
+        }).drain().next().unwrap()
+    }
+}