From a1703430afc2d48a30603536e50da234dbd229bc Mon Sep 17 00:00:00 2001
From: Vicky Maulana <vicky.maulana@gojek.com>
Date: Fri, 7 Mar 2025 16:08:05 +0700
Subject: [PATCH 1/2] lc: add solution for finding closest prime numbers in a
 range

---
 .../leetcode/ClosestPrimeNumbersInRange.java  | 70 +++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 src/main/java/com/thealgorithms/leetcode/ClosestPrimeNumbersInRange.java

diff --git a/src/main/java/com/thealgorithms/leetcode/ClosestPrimeNumbersInRange.java b/src/main/java/com/thealgorithms/leetcode/ClosestPrimeNumbersInRange.java
new file mode 100644
index 000000000000..889c28206463
--- /dev/null
+++ b/src/main/java/com/thealgorithms/leetcode/ClosestPrimeNumbersInRange.java
@@ -0,0 +1,70 @@
+package com.thealgorithms.leetcode;
+
+import java.util.Arrays;
+
+public class ClosestPrimeNumbersInRange {
+    public int[] closestPrimes(int left, int right) {
+        // get all primes up to right
+        boolean[] isPrime = sieveOfEratosthenes(right);
+        
+        // first two primes in range
+        int first = -1;
+        int second = -1;
+        
+        int minDiff = Integer.MAX_VALUE;
+        int prev = -1;
+        
+        for (int i = Math.max(2, left); i <= right; i++) {
+            if (isPrime[i]) {
+                if (prev == -1) {
+                    prev = i;
+                } else {
+                    int diff = i - prev;
+                    if (diff < minDiff) {
+                        minDiff = diff;
+                        first = prev;
+                        second = i;
+                    }
+                    prev = i;
+                }
+            }
+        }
+        
+        return first == -1 ? new int[]{-1, -1} : new int[]{first, second};
+    }
+
+    public boolean isPrime(int n) {
+        if (n <= 1) return false;
+        if (n <= 3) return true;
+        if (n % 2 == 0 || n % 3 == 0) return false;
+
+        // check for prime by testing divisors up to square root of n, can skip even numbers
+        // and optimize by checking only numbers of form 6k + 1
+        for (int i = 5; i * i <= n; i+= 6) {
+            if (n % i == 0 || n % (i + 2) == 0) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+    
+    // helper method to find prime numbers using sieve of eratosthenes
+    public static boolean[] sieveOfEratosthenes(int n) {
+        boolean[] isPrime = new boolean[n+1];
+        Arrays.fill(isPrime, true);
+        isPrime[0] = false;
+        isPrime[1] = false;
+        
+        for (int i = 2; i * i <= n; i++) {
+            if (isPrime[i]) {
+                for (int j = i * i; j <= n; j += i) {
+                    isPrime[j] = false;
+                }
+            }
+        }
+        return isPrime;
+    }
+}
+
+// https://leetcode.com/problems/closest-prime-numbers-in-range/description/

From 4256d1af52e19c4dc87b088364772ef8c471abb1 Mon Sep 17 00:00:00 2001
From: electyrion <electyrion@users.noreply.github.com>
Date: Fri, 7 Mar 2025 09:08:53 +0000
Subject: [PATCH 2/2] Update directory

---
 DIRECTORY.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index b7f2a8e86564..b134176d83fc 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -354,6 +354,8 @@
             * [StockProfitCalculator](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/StockProfitCalculator.java)
           * io
             * [BufferedReader](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/io/BufferedReader.java)
+          * leetcode
+            * [ClosestPrimeNumbersInRange](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/leetcode/ClosestPrimeNumbersInRange.java)
           * lineclipping
             * [CohenSutherland](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/lineclipping/CohenSutherland.java)
             * [LiangBarsky](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/lineclipping/LiangBarsky.java)