add 2824

Author: fishercoder1534

paginated_contents/algorithms/3rd_thousand/README.md

@@ -2,6 +2,7 @@
 |------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------|---------------------------|----------------------------------------------------------------------
 | 2965 | [Find Missing and Repeated Values](https://leetcode.com/problems/find-missing-and-repeated-values/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2965.java)                                       |                                     | Easy                      |
 | 2864 | [Maximum Odd Binary Number](https://leetcode.com/problems/maximum-odd-binary-number/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2864.java)                                       |                                     | Easy                      |Greedy
+| 2824 | [Count Pairs Whose Sum is Less than Target](https://leetcode.com/problems/count-pairs-whose-sum-is-less-than-target/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2824.java)                                       |                                     | Easy                      |
 | 2812 | [Find the Safest Path in a Grid](https://leetcode.com/problems/find-the-safest-path-in-a-grid/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2812.java)                                       |                                     | Medium                    |BFS
 | 2751 | [Robot Collisions](https://leetcode.com/problems/robot-collisions/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2751.java)                                       | | Hard                      | Stack, Simulation
 | 2716 | [Minimize String Length](https://leetcode.com/problems/minimize-string-length/)                                                                                                               | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/thirdthousand/_2716.java)                                       | [:tv:](https://youtu.be/aMJ3T0K8LjI) | Easy                      |

src/main/java/com/fishercoder/solutions/thirdthousand/_2824.java

@@ -0,0 +1,19 @@
+package com.fishercoder.solutions.thirdthousand;
+
+import java.util.List;
+
+public class _2824 {
+    public static class Solution1 {
+        public int countPairs(List<Integer> nums, int target) {
+            int pairs = 0;
+            for (int i = 0; i < nums.size() - 1; i++) {
+                for (int j = i + 1; j < nums.size(); j++) {
+                    if (nums.get(i) + nums.get(j) < target) {
+                        pairs++;
+                    }
+                }
+            }
+            return pairs;
+        }
+    }
+}