Little girl Tanya is learning how to decrease a number by one, but she does it wrong with a number consisting of two or more digits. Tanya subtracts one from a number by the following algorithm:  if the last digit of the number is non-zero, she decreases the number by one;  if the last digit of the number is zero, she divides the number by 10 (i.e. removes the last digit). 

You are given an integer number $n$. Tanya will subtract one from it $k$ times. Your task is to print the result after all $k$ subtractions.

It is guaranteed that the result will be positive integer number.


-----Input-----

The first line of the input contains two integer numbers $n$ and $k$ ($2 \le n \le 10^9$, $1 \le k \le 50$) — the number from which Tanya will subtract and the number of subtractions correspondingly.


-----Output-----

Print one integer number — the result of the decreasing $n$ by one $k$ times.

It is guaranteed that the result will be positive integer number. 


-----Examples-----
Input
512 4

Output
50

Input
1000000000 9

Output
1



-----Note-----

The first example corresponds to the following sequence: $512 \rightarrow 511 \rightarrow 510 \rightarrow 51 \rightarrow 50$.

Difficulty: introductory

Starter code:

Solutions:
n, k = list(map(int, input().split()))
for i in range(k):
    if n%10==0:
        n //= 10
    else:
        n -= 1
print(n)


(n, k) = list(map(int, input().split()))

while k > 0:
    if n % 10 == 0:
        n //= 10
    else:
        n -= 1
    k -= 1

print(n)


n, k = input().split()
k = int(k)
n = n[::-1]

for i in range(k):
    if n[0] == '0':
        n = n[1:]
    else:
        n = chr(ord(n[0]) - 1) + n[1:]

print(n[::-1])


def minus(s):
    if s % 10 == 0:
        return s // 10
    else:
        return s - 1
n, k = map(int, input().split())
for i in range(k):
    n = minus(n)
print(n)

n, k = map(int, input().split())
for _ in range(k):
	if n % 10:
		n -= 1
	else:
		n //= 10
print(n)

x , k = map(int,input().split())
while k!=0:
    if x%10 == 0:
        x /= 10
    else:
        x -=1
    k -= 1
print(int(x))

#!/usr/bin/env python3
from sys import stdin


def solve(tc):
    n, k = map(int, stdin.readline().split())

    for i in range(k):
        if n%10==0:
            n //= 10
        else:
            n -= 1
    
    print(n)
    # items = map(int,stdin.readline().split())
    pass


LOCAL_TEST = not __debug__
if LOCAL_TEST:
    infile = __file__.split('.')[0] + "-test.in"
    stdin = open(infile, 'r')

tcs = (int(stdin.readline().strip()) if LOCAL_TEST else 1)
tc = 1
while tc <= tcs:
    solve(tc)
    tc += 1

n, k = [int(i) for i in input().split()]

for i in range(k):
    if n % 10  == 0:
        n /= 10
    else:
        n -= 1
print(int(n))


n,k=list(map(int,input().split()))
for i in range(k):
    if n%10!=0:
        n-=1
    else:
        n//=10
print(int(n))          

def read_nums():
    return [int(x) for x in input().split()]


def main():
    n, k = read_nums()
    for _ in range(k):
        if n % 10 == 0:
            n = n // 10
        else:
            n = n - 1
    print(n)


def __starting_point():
    main()

__starting_point()

n, k = list(map(int, input().split()))
for i in range(k):
    if n % 10 == 0:
        n //= 10
    else:
        n -= 1
print(n)


n, k = map(int, input().split())

for x in range(k):
    if n%10:
        n -= 1
    else:
        n //= 10

print(n)

n, k = [int(x) for x in input().split()]

for i in range(k):
    if n % 10 == 0:
        n //= 10
    else:
        n -= 1
print(n)

import sys
input = sys.stdin.readline

N,K = map(int,input().split())
for _ in range(K):
	if N % 10 == 0:
		N //= 10
	else:
		N -= 1
print(N)

n ,k = map(int, input().split())
# a = [int(i) for i in input().split()]
while k:
    k -= 1
    if n >= 10:
        if n % 10:
            n -= 1
        else:
            n //= 10
    else:
        n -= 1
print(n)

a, b = map(int, input().split())
for i in range(b):
    if (a % 10 == 0):
        a //= 10
    else:
        a -= 1
print(a)

n, k = map(int, input().split())
for i in range(k):
	if n % 10 == 0:
		n //= 10
	else:
		n -= 1
print(n)

#JMD
#Nagendra Jha-4096

#a=list(map(int,sys.stdin.readline().split(' ')))
#n,k,s= map(int, sys.stdin.readline().split(' '))

import sys
import math

#import fractions
#import numpy

###Defines...###
mod=1000000007

###FUF's...###
def nospace(l):
	ans=''.join(str(i) for i in l)
	return ans



##### Main ####
n,k= list(map(int, sys.stdin.readline().split(' ')))
for i in range(k):
    if(n%10):
        n-=1
    else:
        n=n//10
print(n)


n,k=list(map(int,input().split()))
for i in range(k):
    if n%10==0:
        n//=10
    else:
        n-=1
print(n)


#!/usr/bin/env python3

from sys import stdin


def main():
    x, y = stdin_get_ints_from_line()

    for _ in range(y):
        if str(x).endswith('0'):
            x = x//10
        else:
            x = x - 1

    print(x)


def stdin_get_ints_from_line():
    return (int(x) for x in stdin.readline().strip().split(' '))


def stdin_get_ints_list_from_line():
    return list(int(x) for x in stdin.readline().strip().split(' '))


def stdin_get_string_from_line():
    return stdin.readline().strip()


def __starting_point():
    main()

__starting_point()

n, k = map(int, input().split())

while k > 0:
    k -= 1
    if n % 10 == 0:
        n = n // 10
    else:
        n -= 1

print(n)

n,m = [int(i) for i in input().split()]
while m > 0 :
	#print(n,m)
	if n%10 >= m :
		n-=m
		m = 0
	else:
		m =m-n%10-1
		n = n//10
print(n)


number, iterations = [int(x) for x in input().strip().split(' ')]
for i in range(iterations):
	if number % 10 == 0:
		number = number // 10
	else:
		number -= 1

print(number)

n, k = map(int, input().split())
for i in range(k):
    if n%10:
        n -= 1
    else:
        n //= 10
print(n)

n,k = list(map(int,input().split()))
for i in range(k):
    if n%10 == 0: n//=10
    else: n -=1
print(n)