From 7201f9643d3d4326b5278d8791ae0640552a7179 Mon Sep 17 00:00:00 2001
From: takudzwa <takchiks@gmail.com>
Date: Tue, 17 Feb 2026 19:46:30 -0500
Subject: [PATCH] [Two sum and knapsack ]

---
 Problem1.java | 18 ++++++++++++++++++
 Problem2.java | 17 +++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/Problem1.java b/Problem1.java
index e69de29b..4daf0305 100644
--- a/Problem1.java
+++ b/Problem1.java
@@ -0,0 +1,18 @@
+public class Problem1 {
+
+    // Time Complexity : O(n)
+    // Space Complexity : O(n)
+    // Did this code successfully run on Leetcode : yes
+    public int[] twoSum(int[] nums, int target) {
+        Map<Integer, Integer> map = new HashMap<>();
+
+        for (int i = 0; i < nums.length; i++) {
+            int complement = target - nums[i];
+            if (map.containsKey(complement)) {
+                return new int[] {map.get(complement), i};
+            }
+            map.put(nums[i], i);
+        }
+        return new int[] {};
+    }
+}
\ No newline at end of file
diff --git a/Problem2.java b/Problem2.java
index e69de29b..5a4bcdc6 100644
--- a/Problem2.java
+++ b/Problem2.java
@@ -0,0 +1,17 @@
+public class Problem2 {
+
+    // Time Complexity : O(n * W_capacity)
+    // Space Complexity : O(W_capacity)
+    // Did this code successfully run on Leetcode : yes
+    public int knapsack(int W, int val[], int wt[]) {
+        int n = val.length;
+        int[] dp = new int[W + 1];
+        for (int i = 0; i < n; i++) {
+            for (int j = W; j >= wt[i]; j--) {
+                dp[j] = Math.max(dp[j], val[i] + dp[j - wt[i]]);
+            }
+        }
+
+        return dp[W];
+    }
+}
\ No newline at end of file