Problem10787--ABC144 - C - Walk on Multiplication Table

10787: ABC144 - C - Walk on Multiplication Table

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

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 $N$.

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 $N$.

Constraints

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

Sample 1 Input

10

Sample 1 Output

5

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

Sample 2 Input

50

Sample 2 Output

13

$(5, 10)$ can be reached in $13$ moves.

Sample 3 Input

10000000019

Sample 3 Output

10000000018
Both input and output may be enormous.

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