Building Permutation
题目描述
Permutation p is an ordered set of integers p1,p2,...,pn, consisting of n distinct positive integers, each of them doesn't exceed n. We'll denote the i-th element of permutation p as pi. We'll call number n the size or the length of permutation p1,p2,...,pn.
You have a sequence of integers a1,a2,...,an. In one move, you are allowed to decrease or increase any number by one. Count the minimum number of moves, needed to build a permutation from this sequence.
The first line contains integer n (1≤n≤3·105) − the size of the sought permutation. The second line contains n integers a1,a2,...,an (-109≤ai≤109).
Print a single number − the minimum number of moves.
Please, do not use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.
2
3 0
2
3
-1 -1 2
6
In the first sample you should decrease the first number by one and then increase the second number by one. The resulting permutation is (2,1).
In the second sample you need 6 moves to build permutation (1,3,2).
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