import java.util.*;

class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        
        long min = Long.MAX_VALUE;
        long x = 0;
        long y = 0;
        for(long i = 1; i*i <= N; i++){
            if(i + (N / i) < min && N % i == 0){
                min = i + (N / i);
                x = i;
                y = N / i;
            }
        }

        System.out.println(x - 1 + y - 1);        
    }
}
/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