Walk on Multiplication Table

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.

Examples

Input

10

Output

5

Input

50

Output

13

Input

10000000019

Output

10000000018

inputFormat

Input

Input is given from Standard Input in the following format:

N

outputFormat

Output

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

Examples

Input

10

Output

5

Input

50

Output

13

Input

10000000019

Output

10000000018

样例

10000000019

10000000018