import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long N  = sc.nextLong();
        int limit = (int)Math.sqrt(N);
        long min = N;
        for(int i = 1; i <= limit; i++){
            if(N % i == 0) {
            long j = N/i;
            min = Math.min(min, i + j -2);
            }
        }
        System.out.println(min);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz