Ilya is a very clever lion, he lives in an unusual city ZooVille. In this city all the animals have their rights and obligations. Moreover, they even have their own bank accounts. The state of a bank account is an integer. The state of a bank account can be a negative number. This means that the owner of the account owes the bank money.

Ilya the Lion has recently had a birthday, so he got a lot of gifts. One of them (the gift of the main ZooVille bank) is the opportunity to delete the last digit or the digit before last from the state of his bank account no more than once. For example, if the state of Ilya's bank account is -123, then Ilya can delete the last digit and get his account balance equal to -12, also he can remove its digit before last and get the account balance equal to -13. Of course, Ilya is permitted not to use the opportunity to delete a digit from the balance.

Ilya is not very good at math, and that's why he asks you to help him maximize his bank account. Find the maximum state of the bank account that can be obtained using the bank's gift.

Input

The single line contains integer n (10 ≤ |n| ≤ 109) — the state of Ilya's bank account.

Output

In a single line print an integer — the maximum state of the bank account that Ilya can get. 

Examples

Input

2230


Output

2230


Input

-10


Output

0


Input

-100003


Output

-10000

Note

In the first test sample Ilya doesn't profit from using the present.

In the second test sample you can delete digit 1 and get the state of the account equal to 0.
"""
// Author : snape_here - Susanta Mukherjee
     
"""
 
from __future__ import division, print_function
 
import os,sys
from io import BytesIO, IOBase
 
if sys.version_info[0] < 3:
    from __builtin__ import xrange as range
    from future_builtins import ascii, filter, hex, map, oct, zip
 
 
def ii(): return int(input())
def si(): return input()
def mi(): return map(int,input().split())
def li(): return list(mi())
 
 
def gcd(x, y):
    while y:
        x, y = y, x % y
    return x
    
 
def read():
    sys.stdin = open('input.txt', 'r')  
    sys.stdout = open('output.txt', 'w') 
 
 
import math

from itertools import permutations

mod=100000007 

# Python3 code to find largest prime 
# factor of number 
import math 
  
# A function to find largest prime factor 
def maxPrimeFactors (n): 
      
    # Initialize the maximum prime factor 
    # variable with the lowest one 
    maxPrime = -1
      
    # Print the number of 2s that divide n 
    while n % 2 == 0: 
        maxPrime = 2
        n >>= 1     # equivalent to n /= 2 
          
    # n must be odd at this point,  
    # thus skip the even numbers and  
    # iterate only for odd integers 
    for i in range(3, int(math.sqrt(n)) + 1, 2): 
        while n % i == 0: 
            maxPrime = i 
            n = n / i 
      
    # This condition is to handle the  
    # case when n is a prime number  
    # greater than 2 
    if n > 2: 
        maxPrime = n 

    return maxPrime

# Python3 program to find the most 
# frequent element in an array. 
import math as mt 

def mostFrequent(arr, n): 
  
    # Sort the array 
    arr.sort() 
  
    # find the max frequency using 
    # linear traversal 
    max_count = 1; res = arr[0]; curr_count = 1
      
    for i in range(1, n):  
        if (arr[i] == arr[i - 1]): 
            curr_count += 1
              
        else : 
            if (curr_count > max_count):  
                max_count = curr_count 
                res = arr[i - 1] 
              
            curr_count = 1
      
    # If last element is most frequent 
    if (curr_count > max_count): 
      
        max_count = curr_count 
        res = arr[n - 1] 
      
    return res 



def main():

    n=ii()
    if n<0:
        s=list(str(n))
        c=s[-1]
        s=s[0:len(s)-2]
        s+=c
        s="".join(s)
        b=int(s)
        s1=list(str(n))
        s1=s1[0:len(s1)-1]
        s1="".join(s1)
        a=int(s1)
        n=max(a,b)
        #print(a,b)
    print(n)
        

# region fastio#
 
BUFSIZE = 8192
 
 
class FastIO(IOBase):
    newlines = 0
 
    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None
 
    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()
 
    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()
 
    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)
 
 
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")
 
 
def print(*args, **kwargs):
    """Prints the values to a stream, or to sys.stdout by default."""
    sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout)
    at_start = True
    for x in args:
        if not at_start:
            file.write(sep)
        file.write(str(x))
        at_start = False
    file.write(kwargs.pop("end", "\n"))
    if kwargs.pop("flush", False):
        file.flush()
 
 
if sys.version_info[0] < 3:
    sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout)
else:
    sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
 
input = lambda: sys.stdin.readline().rstrip("\r\n")
 
# endregion
 
 
if __name__ == "__main__":
    #read()
    main() 
#Comment read()
