20241012 finished.

src/problem/mod.rs

@@ -260,4 +260,5 @@ mod p871_minimum_number_of_refueling_stops;
 mod p1436_destination_city;
 mod p3171_find_subarray_with_bitwise_or_closest_to_k;
 mod p3162_find_the_number_of_good_pairs_i;
-mod p3164_find_the_number_of_good_pairs_ii;
+mod p3164_find_the_number_of_good_pairs_ii;
+mod p3158_find_the_xor_of_numbers_which_appear_twice;

src/problem/p3158_find_the_xor_of_numbers_which_appear_twice.rs

@@ -0,0 +1,42 @@
+/**
+ * [3158] Find the XOR of Numbers Which Appear Twice
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+
+impl Solution {
+    pub fn duplicate_numbers_xor(nums: Vec<i32>) -> i32 {
+        use std::collections::HashSet;
+
+        let mut set = HashSet::with_capacity(nums.len());
+
+        let mut result = 0;
+
+        for num in nums {
+            set.insert(num);
+            result ^= num;
+        }
+
+        for num in set {
+            result ^= num;
+        }
+
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_3158() {
+        assert_eq!(1, Solution::duplicate_numbers_xor(vec![1, 2, 1, 3]));
+        assert_eq!(0, Solution::duplicate_numbers_xor(vec![1, 2, 3]));
+        assert_eq!(3, Solution::duplicate_numbers_xor(vec![1, 2, 2, 1]));
+    }
+}