/*
TASK:minitime
LANG:C++
*/
#include<iostream.h>
#include<string.h>
//using namespace std;
int ab[54];
int main(){
    int a,i,br=-1,minim=100,j;
    cin>>a;
    for(i=1;i<=a;i++){
	if(a%i==0){
		br++;ab[br]=i;
		}
	}
    for(i=0;i<=br;i++){
		       if(br>2){
					  j=ab[i]+a/ab[i];
	                                  if(j<minim)minim=j;
	                                  }
                       else {
                            for(i=1;i<=(a-1)/2;i++){
	                                            if((a-1)%i==0){
	                                                           br++;ab[br]=i;
		                                                       }
                                                }
			    if(ab[i]+a/ab[i]+1<minim)minim=ab[i]+a/ab[i]+1;
                            }
                       }
    if(a<6)cout<<a<<"\n";
    else cout<<minim<<"\n";
  // system("PAUSE");
    return 0;
}
