comment

Author: laffed

src/array/best_time_to_buy_and_sell_stock.rs

@@ -20,7 +20,7 @@ where
     P: IntoIterator<Item = i32> + Copy,
 {
     let mut profit = 0;
-    // slightly more elegant than setting to el[0] and starting loop at 1
+    // opinion: slightly more elegant than setting to el[0] and starting loop at 1
     let mut current_min = i32::MAX;
     for i in prices.into_iter() {
         profit = profit.max(i - current_min);

src/array/three_sum.rs

@@ -14,13 +14,33 @@ Constraints:
 -10^5 <= nums[i] <= 10^5
 */
 
+use std::collections::HashSet;
+
 /*
 Naive solution
 T: O(N^3)
 S: O(N)
 */
-pub fn solution_a(_nums: Vec<i32>) -> Vec<Vec<i32>> {
-    vec![]
+pub fn solution_a(nums: Vec<i32>) -> Vec<Vec<i32>> {
+    let mut res: Vec<Vec<i32>> = Vec::new();
+
+    for (i, x) in nums.iter().enumerate() {
+        for (j, y) in nums.iter().enumerate().skip(i + 1) {
+            for (_, z) in nums.iter().enumerate().skip(j + 1) {
+                let sum = x + y + z;
+                if sum != 0 {
+                    continue;
+                }
+
+                let mut v = vec![x.clone(), y.clone(), z.clone()];
+                v.sort();
+                res.push(v);
+            }
+        }
+    }
+
+    res.dedup();
+    res
 }
 
 /*