johnson trotter algorithm to ma rescue:P:)...

I was askin 1 of ma friends whos studyn in 4th year at RVCE as to how his placements were goin on...he tol tat yahoo,microsoft etc had already visited tem...wen i quizzed him abt the questions tey had ased in the interviews...he was left clueless;)..well prety ovz situation considerin hes not too gud at computers:P

howeva he recalled 1 of the questions ...which was pretty simple(considerin the fact tat i had teh MAGIC algorithm wit me:P) acc to me..

the ques was...  :  TO permutate 'n' values or 'n' user inputs...in 'n' diff ways...

acc to me the best way to solve the problem is usin the johnson trotter algo..

johnson trotter algorithm gives a non recursive approach to generate permutations. The algorithm goes something like this..

while there exists a mobile integer k do
-->find the largest mobile integer k;
-->swap k and the adjacent integer, its arrow points to;
-->reverse the direction of all integers that are larger than k

for eg:if the user inputs the n value as 3..

the followin will b the programs compilation ..

<1  <2  <3
<1  <3  <2
<3  <1  <2
 3> <2  <1
<2   3> <1
<2  <1  3>

I'm using a character flag to maintain the direction of the mobile integers.. the code is simple:)..

try it:)..

il post the code in a few days..until ten keep tryin:)