Added most optimised Code to find N prime number

Java/DecimaltoAnyBase.java

@@ -0,0 +1,26 @@
+import java.util.*;
+
+  public class DecimaltoAnyBase{
+
+  public static void main(String[] args) {
+      Scanner scn = new Scanner(System.in);
+      int n = scn.nextInt();
+      int b = scn.nextInt();
+      int dn = getValueInBase(n, b);
+      System.out.println(dn);
+   }
+
+   public static int getValueInBase(int n, int b){
+       int rv = 0;
+
+      int p = 1;
+      while(n > 0){
+          int d = n % b;
+          n = n / b;
+          rv += p * d;
+          p = p * 10;
+      }
+
+       return rv;
+   }
+  }

Java/MostOptimisedPrimeNumberCode.java

@@ -0,0 +1,24 @@
+import java.util.*;
+
+public class MostOptimisedPrimeNumberCode{
+
+public static void main(String[] args) {
+    Scanner scn = new Scanner(System.in);
+    int low = scn.nextInt();
+    int high = scn.nextInt();
+
+    for(int num = low; num <= high; num++){
+        int div = 2;
+        while(div * div <= num){
+            if(num % div == 0){
+                break;
+            }
+            div++;
+        }
+
+        if(div * div > num){
+            System.out.println(num);
+        }
+    }
+ }
+}

Java/SumoftwoArrays.java

@@ -0,0 +1,52 @@
+import java.io.*;
+import java.util.*;
+
+public class SumoftwoArrays{
+
+public static void main(String[] args) throws Exception {
+    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+    int n1 = Integer.parseInt(br.readLine());
+    int[] a1 = new int[n1];
+    for(int i = 0; i < n1; i++){
+       a1[i] = Integer.parseInt(br.readLine());
+    }
+
+    int n2 = Integer.parseInt(br.readLine());
+    int[] a2 = new int[n2];
+    for(int i = 0; i < n2; i++){
+       a2[i] = Integer.parseInt(br.readLine());
+    }
+
+    int[] sum = new int[n1 > n2? n1: n2];
+    int i = n1 - 1;
+    int j = n2 - 1;
+    int k = sum.length - 1;
+    int c = 0;
+    while(i >= 0 || j >= 0){
+       int d = c;
+
+       if(i >= 0)
+         d += a1[i];
+
+      if(j >= 0)
+         d += a2[j];
+
+       c = d / 10;
+       d = d % 10;
+       sum[k] = d;
+
+       i--;
+       j--;
+       k--;
+    }
+
+    if(c > 0){
+       System.out.println(c);
+    }
+    for(int val: sum){
+       System.out.println(val);
+    }
+ }
+
+}