#abc144c. [abc144_c]Walk on Multiplication Table

[abc144_c]Walk on Multiplication Table

Problem Statement

Takahashi is standing on a multiplication table with infinitely many rows and columns.

The square (i,j)(i,j) contains the integer itimesji \\times j. Initially, Takahashi is standing at (1,1)(1,1).

In one move, he can move from (i,j)(i,j) to either (i+1,j)(i+1,j) or (i,j+1)(i,j+1).

Given an integer NN, find the minimum number of moves needed to reach a square that contains NN.

Constraints

  • 2leqNleq10122 \\leq N \\leq 10^{12}
  • NN is an integer.

Input

Input is given from Standard Input in the following format:

NN

Output

Print the minimum number of moves needed to reach a square that contains the integer NN.


Sample Input 1

10

Sample Output 1

5

(2,5)(2,5) can be reached in five moves. We cannot reach a square that contains 1010 in less than five moves.


Sample Input 2

50

Sample Output 2

13

(5,10)(5, 10) can be reached in 1313 moves.


Sample Input 3

10000000019

Sample Output 3

10000000018

Both input and output may be enormous.