PROGRAMMING:Sort with Swap(0, i)

Given any permutation of the numbers {0, 1, 2,..., $$N-1$$}, it is easy to sort them in increasing order. But what if `Swap(0, *)` is the ONLY operation that is allowed to use? For example, to sort {4, 0, 2, 1, 3} we may apply the swap operations in the following way:
```
Swap(0, 1) => {4, 1, 2, 0, 3}
Swap(0, 3) => {4, 1, 2, 3, 0}
Swap(0, 4) => {0, 1, 2, 3, 4}
```
Now you are asked to find the minimum number of swaps need to sort the given permutation of the first $$N$$ nonnegative integers.
### Input Specification:
Each input file contains one test case, which gives a positive $$N$$ ($$\le 10^5$$) followed by a permutation sequence of {0, 1, ..., $$N-1$$}. All the numbers in a line are separated by a space.
### Output Specification:
For each case, simply print in a line the minimum number of swaps need to sort the given permutation.
### Sample Input:
```in
ten
3 5 7 2 6 4 9 0 8 1
```
### Sample Output:
```out
nine
```






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