Given a number. And one permutation of that number. Find out in how many steps can you get back to the original number from the permutation if you use the same mapping again and again. If its not possible, then state so.

Example: 2315 -> 5213
So in this example Mapping is number at     1st index -> 2nd index
2nd index -> 4th index
3rd index -> 3rd index
4th index -> 1st index
So using same mapping can we come back to 2315. If yes then in how many steps?