There is a Swiss bank, which has many lockers in their underground vault. The lockers are numbered from 1 to N, initially all locked. A genius thief somehow managed to enter the vault, and now wants to open all the lockers with his magical key.

Now this thief is kind of crazy. Instead of opening all the lockers serially from 1 to N, he decides to open them in multiple passes!

On the first pass, he opens the first unopened locker (which is always locker #1 in the first pass), and every second unopened lockers thereafter.

On the second pass, he opens the first unopened locker, and every third unopened lockers thereafter.

So basically, on the nth pass, he opens the first unopened locker, and every (n+1)th unopened lockers thereafter.

Say, there are 9 lockers.

On the first pass - he opens 1, 3, 5, 7, and 9. At this stage, these lockers are still closed: 2, 4, 6, and 8.

On the second pass - he opens 2 and 8. At this stage, these lockers are still closed: 4 and 6.

On the third pass - he opens locker 4. At this stage, only locker 6 is still closed.

On the final pass, he opens locker 6. Now all the lockers are open.

Input

A number N (1<=N<=2000) representing the number of lockers.

Output

Print the number of the locker opened last.

Two Sample Inputs

9

42

Two Sample Outputs

6

42