add initial data

two-sum/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "two-sum"
+version = "0.1.0"

two-sum/Cargo.toml

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+[package]
+name = "two-sum"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

two-sum/src/main.rs

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+struct Solution;
+
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn two_sum_o_n(nums: Vec<i32>, target: i32) -> Vec<i32> {
+        // value -> idx map
+        let mut map: HashMap<i32, usize> = HashMap::with_capacity(nums.len());
+
+        for (idx, num) in nums.iter().enumerate() {
+            let diff = target - *num;
+            if let Some(idx2) = map.get(&diff) {
+                return vec![idx as _, *idx2 as _];
+            }
+            map.insert(*num, idx);
+        }
+
+        unreachable!("we are guaranteed an answer exists")
+    }
+
+    pub fn two_sum_o_n_log_n(nums: Vec<i32>, target: i32) -> Vec<i32> {
+        let mut indexed_nums: Vec<_> = nums.into_iter().enumerate().collect();
+        indexed_nums.sort_unstable_by_key(|(_, val)| *val);
+
+        let mut left = 0;
+        let mut right = indexed_nums.len() - 1;
+
+        while left < right {
+            let sum = indexed_nums[left].1 + indexed_nums[right].1;
+            if sum == target {
+                return vec![indexed_nums[left].0 as _, indexed_nums[right].0 as _];
+            } else if sum > target {
+                right -= 1;
+            } else {
+                left += 1;
+            }
+        }
+
+        unreachable!("we are guaranteed a solution exists")
+    }
+}
+
+fn main() {
+    println!("Hello, world!");
+}