rusyasoft
diff --git a/‎Nth Prime Number/NthPrime.java
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+40Lines changed: 40 additions & 0 deletions b/‎Nth Prime Number/NthPrime.java
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+40Lines changed: 40 additions & 0 deletions
diff --git a/‎Nth Prime Number/Sieve.java
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+60Lines changed: 60 additions & 0 deletions b/‎Nth Prime Number/Sieve.java
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+60Lines changed: 60 additions & 0 deletions
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+// Java program to the nth prime number using Iteration
+import java.util.Scanner;
+
+public class NthPrime {
+
+    public static void main(String[] args) {
+
+        Scanner sc = new Scanner(System.in);
+
+        //Taking input
+        int nth = sc.nextInt();
+
+        int num, count, i;
+        num=1;
+        count=0;
+
+        //This loop continues until the value
+        // of the count is less than n.
+        // If the condition is true then
+        // it will increase the value of num by 1.
+        while (count < nth){
+            num=num+1;
+            for (i = 2; i <= num; i++){
+                if (num % i == 0) {
+                    // if the number has a divisor other
+                    // than 1 or itself, we break out of the loop
+                    break;
+                }
+            }
+            //The loop breaks and checks whether i is equal to num.
+            // If it is so then the value of count is increased by 1
+            // and then again checks the condition of while loop.
+            //When the while loop terminates we get our final value in the variable num
+            if ( i == num){
+                count = count+1;
+            }
+        }
+        System.out.println("Value of nth prime: " + num);
+    }
+}
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+// Java program to the nth prime number using Sieve of Eratosthenes
+import java.util.ArrayList;
+import java.util.Scanner;
+
+class Sieve
+{
+
+    // initializing the max value  
+    static int MAX_SIZE = 1000005;
+
+    // To store all prime numbers 
+    static ArrayList<Integer> primes = new ArrayList<Integer>();
+
+    // Function to generate N prime numbers  
+    // using Sieve of Eratosthenes 
+    static void SieveOfEratosthenes()
+    {
+        // Create a boolean array "IsPrime[0..MAX_SIZE]"  
+        // and initialize all entries it as true.  
+        // A value in IsPrime[i] will finally be false  
+        // if i is Not a IsPrime, else true.  
+        boolean [] IsPrime = new boolean[MAX_SIZE];
+
+        for(int i = 0; i < MAX_SIZE; i++)
+            IsPrime[i] = true;
+
+        for (int p = 2; p * p < MAX_SIZE; p++)
+        {
+            // If IsPrime[p] is not changed,  
+            // then it is a prime  
+            if (IsPrime[p] == true)
+            {
+                // Update all multiples of p greater than or  
+                // equal to the square of it  
+                // numbers which are multiple of p and are  
+                // less than p^2 are already been marked.  
+                for (int i = p * p; i < MAX_SIZE; i += p)
+                    IsPrime[i] = false;
+            }
+        }
+
+        // Store all prime numbers  
+        for (int p = 2; p < MAX_SIZE; p++)
+            if (IsPrime[p] == true)
+                primes.add(p);
+    }
+
+    // Driver Code 
+    public static void main (String[] args)
+    {
+        Scanner sc = new Scanner(System.in);
+
+        int N=sc.nextInt();
+
+        // Function call 
+        SieveOfEratosthenes();
+
+        System.out.println("Nth prime number is " + primes.get(N-1));
+    }
+}