/*
TASK:minitime
LANG:C++
*/
#include<iostream>
using namespace std;
int main()
{
    int a,min,i,j;
    cin>>a;
    min=a;
            for(i=1;i<=a;i++)
            {
                             if(a%i==0){if(a/i+i<min)min=a/i+i;}
                             else if(a/i+1+i<min)min=a/i+1+i;
            }                
            cout<<min<<endl;
            }     
