Takahashi is standing on a multiplication table with infinitely many rows and columns.
The square (i,j) contains the integer $i \times j.$ Initially, Takahashi is standing at (1,1).
In one move, he can move from (i,j) to either (i+1,j) or (i,j+1).
Given an integer N, find the minimum number of moves needed to reach a square that contains N.

-----Constraints-----
- $2 \leq N \leq 10^{12}$
- N is an integer.

-----Input-----
Input is given from Standard Input in the following format:
N

-----Output-----
Print the minimum number of moves needed to reach a square that contains the integer N.

-----Sample Input-----
10

-----Sample Output-----
5

(2,5) can be reached in five moves. We cannot reach a square that contains 10 in less than five moves.

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