Merge pull request #721 from sumitvajarinkar/tower-of-hanoi-java

Tower of hanoi java

Author: Saviour1001

Recursion/towerOfHanoi.java

@@ -0,0 +1,58 @@
+//Tower of Hanoi
+//O(2^n)
+
+/*
+Tower of Hanoi is a mathematical puzzle where we have three rods and n disks. The objective of the puzzle is to move the entire stack to another rod, obeying the following simple rules: 
+
+1. Only one disc move at time
+2. Follow order smaller always on the top of bigger
+3. Only top disc must be move
+
+Here we considered three poles 
+s=source d=destination h=helper
+
+i/p: 1
+o/p: Move disc 1 from s to d
+
+i/p: 2
+o/p: Move disc 1 from s to h
+	 Move disc 2 from s to d
+	 Move disc 1 from h to d
+
+i/p: 3
+o/p:Move disc 1 from s to d
+	Move disc 2 from s to h
+	Move disc 1 from d to h
+	Move disc 3 from s to d
+	Move disc 1 from h to s
+	Move disc 2 from h to d
+	Move disc 1 from s to d
+
+
+No. of move : 2^n-1
+*/
+
+import java.util.Scanner;
+
+class towerOfHanoi{
+	static void toh(char s,char d,char h,int n){
+		if(n==1){
+			System.out.println("Move disc "+n+" from "+s+" to "+d+"\n");
+			return;
+		}
+		toh(s,h,d,n-1);
+		System.out.println("Move disc "+n+" from "+s+" to "+d+"\n");
+		toh(h,d,s,n-1);
+}
+public static void main(String[] args) {
+			System.out.println("Enter no. of discs\n");
+			Scanner sc = new Scanner(System.in);
+			int n =sc.nextInt();  
+			sc.close();      
+			toh('s','d','h',n);
+			
+		}
+}
+
+
+