Added Prime Number Program

prime.java

@@ -0,0 +1,26 @@
+import java.io.*;
+public class prime {
+    public static void main(String[] args) throws IOException{
+        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
+        int number;
+        boolean flag = false;
+        System.out.println("Enter a number to check if it is prime or not");
+
+        number = Integer.parseInt(in.readLine());
+
+        for (int i = 2; i <= number / 2; ++i) {
+      // condition for nonprime number
+      if (number % i == 0) {
+        flag = true;
+        break;
+      }
+    }
+
+    if (!flag)
+      System.out.println(number + " is a prime number.");
+    else
+      System.out.println(number + " is not a prime number.");
+
+    }
+
+}