3-sum-closest

3-sum-closest/sol.rs

@@ -0,0 +1,33 @@
+
+/*
+ * @lc app=leetcode id=16 lang=rust
+ *
+ * [16] 3Sum Closest
+ */
+struct Solution {}
+
+// @lc code=start
+use std::cmp::Ordering;
+
+impl Solution {
+    pub fn three_sum_closest(mut nums: Vec<i32>, target: i32) -> i32 {
+        nums.sort_unstable();
+        let mut result = nums[0] + nums[1] + nums[2];
+        for (i, &n) in nums.iter().enumerate() {
+            let (mut l, mut r) = (i + 1, nums.len() - 1);
+            while l < r {
+                let sum = n + nums[l] + nums[r];
+                if (target - sum).abs() < (target - result).abs() {
+                    result = sum;
+                }
+                match sum.cmp(&target) {
+                    Ordering::Equal => return sum,
+                    Ordering::Less => l += 1,
+                    Ordering::Greater => r -= 1
+                }
+            }
+        }
+        result
+    }
+}
+// @lc code=end