Buggy python submission (verdict: Runtime Error):
# coding: utf-8
# Your code here!
import math
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            #if i != int(N/i):
                #lst.append(int(N/i))
    #lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
if len(ans) > 0:
    A = ans[-1]
else:
    print(N-1)
if A*A < N:
    B = int(N/A)
    print(A+B-2)
else:
    print(2*A-2)
'''
if len(ans)%2 == 0 and len(ans)>1:
    A = ans[len(ans)//2-1]
    B = ans[len(ans)//2]
    #print(A,B)
    print(A+B-2)
elif len(ans)%2 == 1 and len(ans)>1:
    A = ans[len(ans)//2]
    print(2*A-2)
else:
    print(N-1)
'''
  
    

Fixed submission:
# coding: utf-8
# Your code here!
import math
import sys
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            #if i != int(N/i):
                #lst.append(int(N/i))
    #lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
if N == 2:
    print(1)
    sys.exit()
    
if len(ans) > 0:
    A = ans[-1]
    if A*A < N:
        B = int(N/A)
        print(A+B-2)
    else:
        print(2*A-2)
else:
    print(N-1)

'''
if len(ans)%2 == 0 and len(ans)>1:
    A = ans[len(ans)//2-1]
    B = ans[len(ans)//2]
    #print(A,B)
    print(A+B-2)
elif len(ans)%2 == 1 and len(ans)>1:
    A = ans[len(ans)//2]
    print(2*A-2)
else:
    print(N-1)
'''

Buggy python submission (verdict: Runtime Error):
# coding: utf-8
# Your code here!
import math
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            if i != int(N/i):
                lst.append(int(N/i))
    lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
A = ans[len(ans)//2-1]
B = ans[len(ans)//2]
#print(A,B,A*B)
if A*B == N and len(ans)>1:
    print(A+B-2)
elif B**2 == N and len(ans)>1:
    print(2*B-2)
else:
    print(N-1)
  
    

Fixed submission:
# coding: utf-8
# Your code here!
import math
import sys
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            #if i != int(N/i):
                #lst.append(int(N/i))
    #lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
if N == 2:
    print(1)
    sys.exit()
    
if len(ans) > 0:
    A = ans[-1]
    if A*A < N:
        B = int(N/A)
        print(A+B-2)
    else:
        print(2*A-2)
else:
    print(N-1)

'''
if len(ans)%2 == 0 and len(ans)>1:
    A = ans[len(ans)//2-1]
    B = ans[len(ans)//2]
    #print(A,B)
    print(A+B-2)
elif len(ans)%2 == 1 and len(ans)>1:
    A = ans[len(ans)//2]
    print(2*A-2)
else:
    print(N-1)
'''

Buggy python submission (verdict: Time Limit Exceeded):
# coding: utf-8
# Your code here!
import math
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,N):
        if N%i == 0:
            lst.append(i)
    #print(lst)
    if len(lst)%2 == 0:
        middle = int(len(lst) / 2)
        #print(lst[middle])
        return lst[middle]
    else:
        middle = int(len(lst) / 2)
        #print(lst[middle])
        return lst[middle]

    
def isPrime(n):
  if n == 2:
    return True
  if n % 2 == 0:
    return False
  m = math.floor(math.sqrt(n)) + 1
  for p in range(3, m, 2):
      if n % p == 0:
        return False
  return True
  
if isPrime(N):
    print(N-1)
else:
    ans = divisor(N)
    A = ans
    B = N/ans
    print(int(A+B-2))#
#print(ans)
        

Fixed submission:
# coding: utf-8
# Your code here!
import math
import sys
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            #if i != int(N/i):
                #lst.append(int(N/i))
    #lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
if N == 2:
    print(1)
    sys.exit()
    
if len(ans) > 0:
    A = ans[-1]
    if A*A < N:
        B = int(N/A)
        print(A+B-2)
    else:
        print(2*A-2)
else:
    print(N-1)

'''
if len(ans)%2 == 0 and len(ans)>1:
    A = ans[len(ans)//2-1]
    B = ans[len(ans)//2]
    #print(A,B)
    print(A+B-2)
elif len(ans)%2 == 1 and len(ans)>1:
    A = ans[len(ans)//2]
    print(2*A-2)
else:
    print(N-1)
'''

Buggy python submission (verdict: Runtime Error):
# coding: utf-8
# Your code here!
import math
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))):
        if N%i == 0:
            lst.append(i)
            
    return lst[-1]
    
def isPrime(n):
  if n == 2:
    return True
  if n % 2 == 0:
    return False
  m = math.floor(math.sqrt(n)) + 1
  for p in range(3, m, 2):
      if n % p == 0:
        return False
  return True
  
if isPrime(N):
    print(N-1)
else:
    ans = divisor(N)
    A = ans
    B = N/ans
    print(int(A+B-2))#
#print(ans)
        

Fixed submission:
# coding: utf-8
# Your code here!
import math
import sys
N = int(input())

def divisor(N):
    lst = []
    for i in range(2,math.ceil(math.sqrt(N))+1):
        if N%i == 0:
            lst.append(i)
            #if i != int(N/i):
                #lst.append(int(N/i))
    #lst.sort()
    return lst
    
ans = divisor(N)
#print(ans,len(ans))
if N == 2:
    print(1)
    sys.exit()
    
if len(ans) > 0:
    A = ans[-1]
    if A*A < N:
        B = int(N/A)
        print(A+B-2)
    else:
        print(2*A-2)
else:
    print(N-1)

'''
if len(ans)%2 == 0 and len(ans)>1:
    A = ans[len(ans)//2-1]
    B = ans[len(ans)//2]
    #print(A,B)
    print(A+B-2)
elif len(ans)%2 == 1 and len(ans)>1:
    A = ans[len(ans)//2]
    print(2*A-2)
else:
    print(N-1)
'''