Problem:
 Score : 100 points    Problem Statement The window of Takahashi's room has a width of A . There are two curtains hung over the window, each of which has a horizontal length of B . (Vertically, the curtains are long enough to cover the whole window.)  We will close the window so as to minimize the total horizontal length of the uncovered part of the window.
Find the total horizontal length of the uncovered parts of the window then.      Constraints  1 \leq A \leq 100  1 \leq B \leq 100  A and B are integers.         Input Input is given from Standard Input in the following format:  A  B       Output Print the total horizontal length of the uncovered parts of the window.        Sample Input 1 12 4      Sample Output 1 4  We have a window with a horizontal length of 12 , and two curtains, each of length 4 , that cover both ends of the window, for example. The uncovered part has a horizontal length of 4 .       Sample Input 2 20 15      Sample Output 2 0  If the window is completely covered, print 0 .       Sample Input 3 20 30      Sample Output 3 0  Each curtain may be longer than the window.

Solution (Python):
A,B=map(int,input().split())
if A>=2*B:
    Ans = A-(2*B)
else:
    Ans=0
print(Ans)

Solution (Python):
n=input().split(" ")
A=int(n[0])
B=int(n[1])
print(A-B*2 if A-B*2>=0  else 0)

Solution (Python):
A, B  = map(int, input().split())
N = A-B*2
if N <=0:
    print(0)
else:
    print(N)

Solution (Python):
import sys

A, B = map(int, sys.stdin.readline().split())

print(max(A - 2*B, 0))

Solution (Python):
A, B = (int(i) for i in input().split()) 

ans = A - 2 * B
if ans < 0:
  ans = 0
  
print(ans)

Solution (Python):
A,B = map(int,input().split())
curtain_len = A-B*2
if curtain_len > 0:
  print(curtain_len)
else:
  print(0)

Solution (Python):
a,b = map(int,input().split())

if a-2*b>0:
    print(a-2*b)
else:
    print(0)

Solution (Python):
A, B = map(int, input().split())
print(max(0, A-B*2))

Solution (Python):
A, B = map(int, input().split())
d = A - B * 2
print(0 if d <= 0 else d)

Solution (Python):
a,b=map(int, input().split())
if a<=2*b:
    print(0)
else:
    print(a-2*b)

Solution (Python):
a,b = (int(i) for i in input().split())
print(max(a-2*b, 0))

Solution (Python):
w ,k = map(int, input().split())
print(max(0, w-k*2))

Solution (Python):
w, k = map(int, input().split())
x = w - (k*2)
if 0 <= x:
    print(x)
else:
    print(0)

Solution (Python):
a, b = map(int, input().split())
if a - 2*b >0:
  print(a - 2*b)
else:
  print(0)

Solution (Python):
def main():
    A, B = map(int, input().split())
    ans = max(A-B*2, 0)
    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
a,b = map(int, input().split())
print(max(0, (a-2*b)))

Solution (Python):
a, b = map(int, input().split())
print(max(a-2*b, 0))

Solution (Python):
a,b = input().split()
a,b = int(a),int(b)
print(max(a-2*b,0))

Solution (Python):
a,b=map(int,input().split())
ans=a-b*2
if ans<=0:
    print(0)
else:
    print(a-(b*2))

Solution (Python):
a,b = map(int, input().split())
ans = a-2*b
if ans < 0:
    ans = 0
print(ans)

Solution (Python):
A,B=map(int, input().split())
if A-2*B<0:
    print(0)
else:
    print(A-2*B)

Solution (Python):
A, B = map(int, input().split())
if A - B*2 >0:
    print(A - B*2)
else:
    print(0)

Solution (Python):
i=list(map(int, input().split()))
remain=i[0]-2*i[1]
if remain>0:
	print(remain)
else:
  	print("0")

Solution (Python):
def main():
    A, B = map(int, input().split())
    ans = 0 if A <= 2 * B else A - 2 * B
    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
x,y = map(int,input().split())
ans=x-y*2
if ans <=0:
	print(0)
else:
  print(ans)

Solution (Python):
a, b = map(int, input().split())
print(max(a - b * 2, 0))

Solution (Python):
A,B=input().split()
length = int(A) - 2 * int(B)
if length < 0:
    print(0)
else:
    print(length)

Solution (Python):
A,B = map(int, input().split())
if A <= 2*B:
  print(0)
else:
  print(A-2*B)

Solution (Python):
a, b = map(int, input().split(" "))
if b * 2 >= a:
  print(0)
else:
  print(a - b*2)

Solution (Python):
a, b = map(int, input().split())
print(max(a - (b * 2), 0))

Solution (Python):
a, b = map(int, input().split())

c = a - b * 2

if c <= 0:
    print(0)
else:
    print(c)

Solution (Python):
a,b = map(int,input().split())
c = a-2*b
if c > 0:
    print(c)
else:
    print(0)

Solution (Python):
a,b=[int(i) for i in input().split()]
print(max(0,a-2*b))

Solution (Python):
a, b = map(int, input().split())

if a <= b * 2:
    print(0)
else:
    print(a - b * 2)

Solution (Python):
a,b = map(int,input().split())

if a > b * 2:
  print(a - (b * 2))
else:
  print(0)

Solution (Python):
a,b = map(int,input().split())
if a-2*b > 0:
 print(a-2*b)
else: 
 print(0)

Solution (Python):
a,b = map(int,input().split())
c = 2*b
d = a-c
if d > 0:
 print(d)
elif d <= 0:
 print(0)

Solution (Python):
a,b=map(int,input().split(" "))
print(max(0,a-2*b))

Solution (Python):
A, B = input().split()

B = int(B) * 2

if int(A) >= B:
    print(int(A) - B)
else:
    print(0)

Solution (Python):
a,b=map(int,input().split())
a-=b*2
if a>0:
  print(a)
else:
  print(0)

Solution (Python):
a, b = map(int, input().split())
print(max(0, a-b*2))

Solution (Python):
a, b = map(int, input().split())
print(max(a - b * 2, 0))

Solution (Python):
a, b = map(int, input().split())

if a >= b * 2:
    print(a - b * 2)
else:
    print(0)

Solution (Python):
A, B = map(int, input().split())

print(A-2*B if A-2*B>=0 else 0)

Solution (Python):
A, B = map(int, input().split())
print(0 if A <= B*2 else A - B*2)

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-b*2))

Solution (Python):
a,b=map(int,input().split())

if a-2*b>=0:
  print(a-2*b)
else:
  print(0)

Solution (Python):
a,b = map(int,input().split())
print(max(0,(a-2*b)))

Solution (Python):
A,B= map(int,input().split(" "))
result = A - 2*B

if A - 2*B < 0:
    result = 0;

print(result)

Solution (Python):
a, b = map(int, input().split())
ans = a-b*2;
if(ans>=0) : print(ans)
else : print(0)

Solution (Python):
def main():

    a, b = map(int, input().split())
    if a < b:
        print("0")
    elif a < 2 * b:
        print("0")
    else:
        print(a - 2 * b)

if __name__ == "__main__":
    main()

Solution (Python):

A,B = map(int, input().split())

if A-2*B <= 0:
    print(0)
else:
    print(A-2*B)

Solution (Python):
a, b = map(int, input().split())
print(max(0,a - 2 * b))

Solution (Python):
a,b = map(int,input().split(" "))
l = a - 2 * b
if l < 0:
    print("0")
else:
    print(l)

Solution (Python):
a,b = map(int,input().split(" "))
c=a-b-b
if(c<=0):
    print(0)
else:
    print(c)

Solution (Python):
a, b = (int(x) for x in input().split())

if a < 2*b:
	print(0)
elif a == 2*b :
	print(0)
else :
	c = a - 2*b
	print(c)

Solution (Python):
A,B = list(map(int,input().split()))
print(max(0,A-2*B))

Solution (Python):
def main():
    a, b = map(int, input().split())
    ans = max(a - 2 * b, 0)
    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
a, b = map(int, input().split())
if a <= b*2:
    print(0)
else:
    print(a-b*2)

Solution (Python):
s=list(map(int,input().split()))
a =s[0] -2*s[1]
if a <= 0:
  print(0)
else:
  print(a)

Solution (Python):
s = list(map(int, input().split()))
a = s[0] - 2*s[1]
if a <= 0:
    print(0)
else:
    print(a)

Solution (Python):
a,b = list(map(int, input().split()))
if a >= 2*b:
  print(a-2*b)
else:
  print(0)

Solution (Python):
def solve(string):
    a, b = map(int, string.split())
    return str(max(0, a - 2 * b))


if __name__ == '__main__':
    print(solve(input()))

Solution (Python):
a, b = [int(i) for i in input().split()]

if 2*b >= a:
    print(0)

else:
    print(a - 2*b)

Solution (Python):
A,B=map(int,input().split())
if A-B*2<=0:
    print(0)
else:
    print(A-B*2)

Solution (Python):
a,b=map(int,input().split())
if a-(2*b)<0:
  print(0)
elif a-(2*b)>=0:
  print( a-(2*b))

Solution (Python):
A,B = map(int,input().split())
ans = A-2*B
if ans>0:
    print(ans)
else:
    print(0)

Solution (Python):

lst_A = []
lst_A = input().split()
A = int(lst_A[0])
B = int(lst_A[1])
ans = A - B * 2
if ans < 0:
    ans = 0
print(ans)

Solution (Python):
a, b = map(int, input().split())
print(max(0,a-b*2))

Solution (Python):
a,b=map(int,input().split());print(max(0, a-2*b))

Solution (Python):
a,b=map(int,input().split());print(max(0, a-2*b))

Solution (Python):
a, b = map(int, input().split())

l = a - (b * 2)
if (l > 0):
    print(l)
else:
    print(0)

Solution (Python):
a,b = map(int,input().split())

ans = max(0, a - 2*b)

print(ans)

Solution (Python):
a, b = map(int, input().split())
print((a - 2 * b) if a - 2 * b >= 0 else 0)

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
A, B = map(int, input().split())
if A <= 2 * B:
  print(0)
else:
  print(A - 2 * B)

Solution (Python):
A,B=map(int,input().split())
if A<=2*B:
    print(0)
else:
    print(A-2*B)

Solution (Python):
a,b=map(int,input().split())
c = a - b*2
if c < 0:
    print(0)
else:
    print(c)

Solution (Python):
a,b=map(int,input().split())
i=a-b*2
if i<0:
  i=0
print(i)

Solution (Python):
a, b = map(int, input().split())
ans = a-b*2
print(ans if ans >= 0 else 0)

Solution (Python):



def main():
    a, b = map(int, input().split())
    print(max(a - 2 * b, 0))


if __name__ == '__main__':
    main()

Solution (Python):
def next_ints():
    return list(map(int, input().split()))

a, b = next_ints()
print(max(0, a - 2 * b))

Solution (Python):
a, b = map(int, input().split())
c = a - 2 * b
if c > 0:
  print(c)
else:
  print(0)

Solution (Python):



A, B = map(int, input().split())
if A - B * 2 >= 0:
    print(A - B * 2)
else:
    print(0)

Solution (Python):
a,b = map(int,input().split())

s = a - b*2

if s <= 0:
	print(0)
else:
	print(s)

Solution (Python):
window, cartain = map(int, input().split())

print(window - cartain*2 if window - cartain*2 > 0 else 0)

Solution (Python):
window, cartain = map(int, input().split())

ret = window - cartain * 2
if ret > 0:
    print(ret)
else:
    print(0)

Solution (Python):
A,B =map(int,input().split())
print(max(A-2*B,0))

Solution (Python):
A, B = map(int, input().split())

klen = B * 2

if klen >= A:
    print(0)
else:
    print(A - klen)

Solution (Python):
from sys import stdin
a, b = map(int, stdin.readline().rstrip().split())
print(max(0, a-2*b))

Solution (Python):
a,b=(int(x) for x in input().split())

if(a>2*b):
 print(a-2*b)
else:
 print("0")

Solution (Python):
a,b = map(int,input().split())
if a>b*2:
  print(a-(2*b))
else:
  print(0)

Solution (Python):
A,B = map(int,input().split())

def cartain(A,B):
  if A-2*B <= 0:
    return 0
  else:
    return A-2*B

print(cartain(A,B))

Solution (Python):
a,b = map(int,input().split())

ans = max(0, a - 2*b)

print(ans)

Solution (Python):
n,m=map(int,input().split())
if n/2>m:
  ans=n-m*2
else:
  ans=0
print(ans)

Solution (Python):
a,b = input().split()
a = int(a); b = int(b)
c = max(0, a-2*b)
print(c)

Solution (Python):
A, B = tuple(int(num) for num in input().split())

B = B*2

if A > B:
  print(A-B)
else:
  print(0)

Solution (Python):
a,b = map(int,input().split())
if a <= 2 *b:
    print(0)
else:
    print(a-2*b)

Solution (Python):
a,b = map(int,input().split())
resp = a - 2*b
if resp > 0:
	print(resp)
else:
	print('0')

Solution (Python):
a,b =map(int, input().split())
c = 2 * b 
if a > c:
    print(a-c)
else:
    print(0)

Solution (Python):
A,B = map(int, input().split())
print(max(0, A-2*B))

Solution (Python):
val = input().split()

A = int(val[0])
B = int(val[1])

def answer(A, B):
    if A <= B * 2:
        return 0
    else:
        return A - B * 2

print(answer(A, B))

Solution (Python):
A, B = map(int, input().split(" ") )

if A-2*B > 0:
    print(A-2*B)
else:
    print(0)

Solution (Python):
A,B = [int(c) for c in input().strip().split(' ')]
if A>2*B:
    print(A-2*B)
else:
    print(0)

Solution (Python):
a, b = map(int, input().split())
if a > 2*b:
    print(a-2*b)
else:
    print(0)

Solution (Python):
a, b = map(int, input().split())

print(max(0, a - b*2))

Solution (Python):
data = list(map(int, input().split()))
diff = data[0] - 2*data[1]
if diff < 0:
    print(0)
else:
    print(diff)

Solution (Python):
A,B = map(int,input().split())
if A <= B:
  print(0)
elif A > B and A <= B*2:
  print(0)
else:
  print(A-B*2)

Solution (Python):
A,B = map(int,input().split())
r=A-2*B
if r <=0:
  print(0)
else:
  print(r)

Solution (Python):
l,r = map(int,input().split())
if l - (2*r) <= 0:
  print(0)
else:
  print(l-r*2)

Solution (Python):
result = list(map(int,input().split()))
A = result[0]
B = result[1]

c = A - B*2
if c < 0:
  c = 0
print(c)

Solution (Python):
import sys
sys.setrecursionlimit(10**7)
INTMAX = 9223372036854775807
INTMIN = -9223372036854775808
MOD = 1000000007
def POW(x, y): return pow(x, y, MOD)
def INV(x, m=MOD): return pow(x, m - 2, m)
def DIV(x, y, m=MOD): return (x * INV(y, m)) % m
def LI(): return [int(x) for x in input().split()]
def LF(): return [float(x) for x in input().split()]
def LS(): return input().split()
def II(): return int(input())

A,B=LI()
res = A-B*2
print(res if res > 0 else 0)

Solution (Python):
in1,in2 = input().split()
if int(in1) > (int(in2) * 2):
	print (int(in1) - int(in2) * 2)
else:
	print(0)

Solution (Python):
a,b=map(int,raw_input().split())
print max(0,a-2*b)

Solution (Python):
a,b=map(int,input().split())

c=a-2*b
if c<0:
    print(0)
else:
    print(c)

Solution (Python):
import sys
input = sys.stdin.readline

a, b = map(int, input().split())

ans = a - 2*b
if ans < 0:
    ans = 0

print(ans)

Solution (Python):
A,B = map(int,input().split())
nokori = A - 2*B

if nokori > 0:
  print(nokori)
else:
  print(0)

Solution (Python):
a,b=map(int,input().split())
if (a-(2*b))<=0:
  print(0)
else:
  print(a-(2*b))

Solution (Python):
A, B = map(int, input().split())
print(max(A-B*2, 0))

Solution (Python):
a, b = map(int, input().split())
ans = a - 2 * b
if ans < 0:
    ans = 0
print(ans)

Solution (Python):
A, B = map(int, input().split())

if(A<=2*B):
	print("0")
else:
	print(A-2*B)

Solution (Python):
a, b = map(int, input().split())
if a - 2 * b >= 0:
    print(a - 2 * b)
else:
    print(0)

Solution (Python):
import sys
input = sys.stdin.readline

N,M=map(int,input().split())
ans=max(0,N-2*M)
print(ans)

Solution (Python):
A, B = map(int, input().split())
print(max(0, A - 2*B))

Solution (Python):
A,B = map(int, input().split())
print(max(A-2*B, 0))

Solution (Python):
A, B = map(int, input().split())
ans = max(A - 2 * B, 0)
print(ans)

Solution (Python):
A,B = map(int,input().split())

if (A <= 2*B) :
    print(0)
else :
    print(A - 2*B)

Solution (Python):

import sys
import copy
import collections
from bisect import bisect_left
from bisect import bisect_right
from collections import defaultdict
from heapq import heappop, heappush, heapify
import math
import itertools
import random
 




 
INF = float('inf')
def inputInt(): return int(input())
def inputMap(): return map(int, input().split())
def inputList(): return list(map(int, input().split()))
 
def main():
    A,B = inputMap()
    
    ans = A - (2*B)
    
    print(max(0,ans))
    
if __name__ == "__main__":
	main()

Solution (Python):
A, B = (int(i) for i in input().split())
C = A - 2*B
if C >= 0 :
    print(C)
else :
    print('0')

Solution (Python):


import sys
import math
import collections
import itertools
from inspect import currentframe
INF = 10 ** 10
MOD = 10 ** 9 + 7
def input() : return sys.stdin.readline().strip()
def gcd(x, y) : return y if x % y == 0 else gcd(y, x % y)
def lcm(x, y) : return (x * y) // gcd(x, y)
def I() : return int(input())
def MI() : return map(int, input().split())
def LI() : return [int(x) for x in input().split()]
def RI(N) : return [int(input()) for _ in range(N)]
def LRI(N) : return [[int(x) for x in input().split()] for _ in range(N)]
def chkprint(*args) : names = {id(v):k for k,v in currentframe().f_back.f_locals.items()}; print(', '.join(names.get(id(arg),'???')+' = '+repr(arg) for arg in args))

A, B = MI()
ans = A - B * 2

print(ans if ans > 0 else 0)

Solution (Python):
a,b=map(int,input().split())
if a-2*b>0:
  print(a-2*b)
else:
  print(0)

Solution (Python):
a,b=map(int,input().split())
if a-2*b>0:
  print(a-2*b)
else:
  print("0")

Solution (Python):
A,B = map(int,input().split())
C = A - (B * 2)
if C < 0:
  C = 0
print(C)

Solution (Python):
A, B =map(int,input().split())
print(max(0,A-2*B))

Solution (Python):
a,b= map(int,input().split())
c= a - b*2
if c > 0:
    print(c)
else:
    print (0)

Solution (Python):
def main():
    a, b = scan()
    print(0 if a < 2 * b else a - 2 * b)
    

def iread():
    return int(input())


def sread():
    return input()


def aread(t="int"):
    if t == "int":
        ret = [int(i) for i in input().split()]
    elif t == "str":
        ret = list(input().split())
    return ret


def scan():
    return list(map(int, input().split()))


if __name__ == '__main__':
    main()

Solution (Python):
a, b = map(int, input().split())
print(max(0, a - 2 * b))

Solution (Python):
a, b = list(map(int, input().split()))

print(max(0, a-2*b))

Solution (Python):
a,b=input().strip().split(" ")
a,b=[int(a),int(b)]
p=2*b
if a-p<=0:
  print(0)
else:
  print(a-p)

Solution (Python):
a,b = map(int,input().split())
ans = max(a-2*b,0)
print(ans)

Solution (Python):
A, B = map(int, input().split())

n = max(0, A - 2 * B)

print(n)

Solution (Python):
import math,string,itertools,fractions,heapq,collections,re,array,bisect,sys,random,time,queue,copy

sys.setrecursionlimit(10**7)
inf=10**20
mod=10**9+7
dd=[(-1,0),(0,1),(1,0),(0,-1)]
ddn=[(-1,0),(-1,1),(0,1),(1,1),(1,0),(1,-1),(0,-1),(-1,-1)]

def LI(): return [int(x) for x in sys.stdin.readline().split()]
def LI_(): return [int(x)-1 for x in sys.stdin.readline().split()]
def I(): return int(sys.stdin.readline())
def LS(): return sys.stdin.readline().split()
def S(): return input()

def main():
  a,b=LI()
  return max(0,a-2*b)


print(main())

Solution (Python):
i = list(map(int, input().split()))
num = i[0] - i[1] * 2
if num > 0:
  print(num)
else:
  print(0)

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
a, b = list(map(int, input().split()))
print(a-b*2 if a-b*2 >= 0 else 0)

Solution (Python):
a,b = map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
a, b = map(int, (input().split()))
print(max(0, a - (b*2)))

Solution (Python):
A, B=[int(i) for i in input().split()]
if B*2>A:
  print(0)
else:
  print(A-B*2)

Solution (Python):
a,b=map(int,input().split())
if a>2*b:
  print(a-2*b)
else:
  print(0)

Solution (Python):
A, B = map(int, input().split())
if (A-2*B)<0:
  print(0)
else:
  print(A-2*B)

Solution (Python):
a,b = map(int,input().split())
print(a-b*2 if a-b*2>0 else 0)

Solution (Python):
A,B = map(int,input().split())
print(max(A-2*B,0))

Solution (Python):
A,B = map(int,input().split())
C = A - (B*2)
if C < 0:
  print("0")
else:
  print(C)

Solution (Python):
import fileinput

def process(A, B):
    if A <= B*2:
        return 0
    else:
        return A - B*2

for line in fileinput.input():
    print(process(*map(int, line.split())))

Solution (Python):
print(eval('max('+input().replace(' ','-2*')+',0)'))

Solution (Python):
d = list(map(int, input().split()))

x = d[0]-d[1]*2

if x>=0:
	print(x)
else:
	print(0)

Solution (Python):
A, B = list(map(int, input().split()))

ans = A - (B * 2)

if ans > 0:
    print(ans)
else:
    print(0)

Solution (Python):
A , B = list(map(int, input().split()))
ans = A -(2*B)
if ans <= 0:
  print(0)
else:
  print(ans)

Solution (Python):
a,b=map(int,input().split())

print(max(0,(a-(b*2))))

Solution (Python):
A, B = map(int, input().split())

if A <= 2 * B:
  print(0)
  
else:
  print(A - 2*B)

Solution (Python):
a,b = map(int,input().split())
print(max(0,a-b*2))

Solution (Python):
A, B = map(int, input().split())
print(max(0,A-2*B))

Solution (Python):
a, b = map(int, input().split())
bb = b * 2
if a <= bb:
    print(0)
else:
    print(abs(bb - a))

Solution (Python):
a = list(map(int, input().split()))
A = a[0]
B = a[1]
if A <= B * 2:
    print(0)
else:
    print(A - B * 2)

Solution (Python):
a, b = map(int, input().split())
if a <= b:
    print(0)
else:
    bb = b * 2
    if a <= bb:
        print(0)
    else:
        print(abs(bb -a))

Solution (Python):
a,b=map(int,input().split())
d=a-2*b
if d>0:
  print(d)
else:
  print('0')

Solution (Python):
a,b=map(int,input().split())
if a-b*2 >0:
  print(a-b*2)
else:
  print(0)

Solution (Python):
A, B = map(int, raw_input().split())
print(max(0, A - 2 * B))

Solution (Python):
a,b = map(int,input().split())
gap = a-2*b
if gap > 0:
    print(gap)
else:
    print(0)

Solution (Python):
A , B = map(int,input().split())

if A-2*B >= 0:
    print(A-2*B)

else:
    print(0)

Solution (Python):
A , B = map(int,input().split())

if A-2*B >= 0:
    print(A-2*B)

else:
    print(0)

Solution (Python):
a, b = map(int, input().split())
print(max(0, a-2*b))

Solution (Python):
def func():
    A,B=map(int,input().split())
    
    if A>=B*2:
        C=A-2*B
        print(C)
    else:
        print(0)
        
if __name__=="__main__":
    func()

Solution (Python):
A, B = map(int, input().split())

if A > B * 2:
  print(A - B * 2)
else:
  print(0);

Solution (Python):
N,M = map(int,input().split())
print(max(0,N-M*2))

Solution (Python):
a,b = map(int,input().split(' '))
print(max(a-2*b,0))

Solution (Python):
a,b = map(int,input().split())

if a - 2*b <= 0:
    print(0)
else:
    print(a - 2*b)

Solution (Python):
a, b = map(int, input().split())
if(a <= b*2):
    print(0)
else:
    print(a - b*2)

Solution (Python):
A,B=map(int,input().split())
print(max(0,A-2*B))

Solution (Python):
A,B=input().split()
ans=int(A)-int(B)*2
if ans > 0:
  print(ans)
else:
  print(0)

Solution (Python):
a,b = map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
A, B = map(int, input().split())

print(max(A-2*B, 0))

Solution (Python):
a,b = map(int,input().split())

ans = a - 2*b

if(ans>=0):
    print(ans)
else:
    print(0)

Solution (Python):
a,b = map(int,input().split())

if a-b*2>0:
    print(a-b*2)
else:
    print(0)

Solution (Python):
a, b = map(int, input().split())
print(max(a - b * 2, 0))

Solution (Python):
length= list(map(int,input().split()))

length_window=length[0]
length_curtain=length[1]

if 2*length_curtain >= length_window:
	print(0)
else:
	print(length_window-2*length_curtain)

Solution (Python):
a, b = map(int, input().split())
ans = 0
if (a - b * 2) > 0:
    ans = (a - b * 2)
print(ans)

Solution (Python):
a, b = map(int, input().split())
print(max(0, a - b * 2))

Solution (Python):
A,B=map(int,input().split())
C=A-2*B
if C>0:
  print(C)
else:
  print(0)

Solution (Python):
a, b = map(int, input().split())

if a - 2*b > 0:
    print(a - 2*b)
else:
    print(0)

Solution (Python):
a, b = map(int, input().split())

ans = a - 2 * b
if ans <= 0:
  print(0)
else:
  print(ans)

Solution (Python):


A, B = map(int, input().split())

print( A - B * 2 if A >= B *2 else 0)

Solution (Python):
A, B = map(int, input().split())
print(max(A-2*B, 0))

Solution (Python):
A, B = map(int,input().split())
print(max(A - (2 * B), 0))

Solution (Python):
temp = list(map(int, input().split()))

A = temp[0]
B = temp[1]

if(A-2*B>0):
  print(A-2*B)
else:
  print(0)

Solution (Python):
MK = input()
mado = int(MK.split(" ")[0])
katen = int(MK.split(" ")[1])
 
n = mado - (katen*2)
 
if n >= 0:
  print(n)
else:
  print(0)

Solution (Python):

a, b = map(int, input().split())
print(max(0, a-2*b))

Solution (Python):
a = list(map(int,input().split()))
A=a[0]
B=a[1]
if A<=B*2:
    print(0)
else:
    print(A-B*2)

Solution (Python):
a,b=map(lambda x:int(x),input().split())
x=max(a-b*2,0)
print(x)

Solution (Python):
A, B = input().split()
A = int(A)
B = int(B)

if A - 2*B >= 0:
  print(A - 2*B)
else:
  print(0)

Solution (Python):
A, B = map(int, input().split())
print(max(0, A - B * 2))

Solution (Python):
A,B=map(int,input().split())

if A-2*B>0:
	print(A-2*B)
else:
  print(0)

Solution (Python):
a,b=map(int,input().split())
print(max(a-2*b,0))

Solution (Python):



a,b = map(int,input().split())
print(max(a-2*b,0))

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
inputStr = input().split()
A = int(inputStr[0])
B = int(inputStr[1])

if (A-(B * 2)) < 0:
    print(0)
else:
    print(A-(B * 2))

Solution (Python):
a, b = map(int, input().split())

c = a - (b*2)
if c >= 0:
  print(c)
else:
  print(0)

Solution (Python):
a,b=map(int,input().split())

print(max(0,a-b*2))

Solution (Python):



i = list(map(int, input().split()))


X = i[0] - i[1]*2


if X > 0:
    print(X)
else:
    print(0)

Solution (Python):





A,B = map(int, input().split())
print(max(A-2*B,0))

Solution (Python):
A, B = list(map(int, input().split()))
print(max(0, A - 2 * B))

Solution (Python):
a,b= map(int,input().split())

if b>a:
    print(0)
elif b*2>a:
    print(0)
else:
    print(a-(b*2))

Solution (Python):






from sys import stdin,setrecursionlimit





setrecursionlimit(10**6)
input=stdin.readline

a,b=map(int,input().split())
print(a-2*b if a-2*b>=0 else 0)

Solution (Python):
A,B = map(int,input().split())
ans = A-2*B
if ans > 0:
    print(ans)
else:
    print(0)

Solution (Python):
a, b = map(int,input().split())
print(a - b * 2 if a - b * 2 > 0 else 0)

Solution (Python):
entry = list(map(int, input().split()))
if entry[0] <= entry[1] * 2:
  print(0)
else:
  print(entry[0] - entry[1] * 2)

Solution (Python):
a,b=map(int,input().split());print(max(a-b-b,0))

Solution (Python):
A, B = [int(i) for i in input().split(' ')]
0<=A<=100
0<=B<=100
 
if A>B*2:
  print(A-B*2)
 
else:
  print(0)

Solution (Python):
A, B = [int(i) for i in input().split()]
0<=A<=100
0<=B<=100

if A>B*2:
  print(A-B*2)

else:
  print(0)

Solution (Python):
a,b = map(int, input().split())
print(max(0, a-b*2))

Solution (Python):
a, b = map(int, input().split())
print(max(a - b * 2, 0))

Solution (Python):
a, b = map(int, input().split())

if a < 2*b: print(0)
else: print(a-2*b)

Solution (Python):
A, B = map(int, input().split())
print(max(0, A-B*2))

Solution (Python):
A,B = map(int, input().split())
print(max(0, A-2*B))

Solution (Python):
a, b = list(map(int, input().split()))

print(max(0, a - 2 * b))

Solution (Python):
a, b = map(int, input().split())

answer = a - 2 * b

if (answer < 0):
  print(0)
else:
  print(answer)

Solution (Python):

a,b=map(int, input().split())

answer=a-2*b

if(answer < 0):
    print(0)
else:
    print(answer)

Solution (Python):

a, b = map(int, input().split())

answer = a - 2 * b

if(answer < 0):
	print(0)
else:
	print(answer)

Solution (Python):
def main():
    n, m = map(int, input().split())
    if n <= m*2:
        print(0)
    else:
        print(n-m*2)


if __name__ == "__main__":
    main()

Solution (Python):
a,b = map(int,input().split())
ans = a - 2*b
if ans<0:
    print(0)
else:
    print(ans)

Solution (Python):
a, b = input().split()
a, b = int(a), int(b)
x = a - b - b
if (x < 0):
  print(0)
else:
  print(x)

Solution (Python):
from sys import stdin

A,B = list(map(int,stdin.readline().strip().split()))

ans = A-B*2

if ans < 0:
    ans = 0
print(ans)

Solution (Python):
a,b=map(int, input().split())
if a-2*b<=0:
    print(0)
else:
    print(a-2*b)

Solution (Python):
a, b = [int(i) for i in input().split()]

print(max(0, a - 2*b))

Solution (Python):
a, b = map(int, input().split())
print(max(0, a - b * 2))

Solution (Python):
data = input().rstrip().split()
Win = int(data[0])
Car = int(data[1])

Res = Win - Car*2

if Res < 0:
  print(0)
else:
  print(Res)

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
a, b = map(int, input().split())

horizontal_length = b * 2

uncovered_part = a - horizontal_length

if uncovered_part < 0:
  uncovered_part = 0
  
print(str(uncovered_part))

Solution (Python):
from sys import stdin


def fin(f):
    return f(input())


def gin(f, n=1):
    for _ in range(n):
        yield list(map(f, stdin.readline().split()))


a, b = next(gin(int))

print(max(0, a - 2 * b))

Solution (Python):
a,b = map(int, input().split())
ans = a - 2 * b
if ans < 0:
    ans = 0
print(ans)

Solution (Python):
a, b = map(int, input().split())
print(max(0, a - 2 * b))

Solution (Python):
a, b = map(int,input().split())

if 2 * b < a:
    print(a- 2 * b)
else:
    print(0)

Solution (Python):
from sys import exit, stdin
A, B = [int(_) for _ in stdin.readline().rstrip().split()]
print(max(0, A-B*2))

Solution (Python):
A, B = map(int, input().split())
ans = A - 2*B
if ans >= 0:
  print(ans)
else:
  print("0")

Solution (Python):
a, b = map(int, input().split())
print(max(0, a-b*2))

Solution (Python):
a , b = map(int, input().split())

if (a <= b * 2):
  print (0)
else:
  print (a - b * 2)

Solution (Python):


 
a,b = map(int, input().split())
 
kai = a - (2 * b)

if kai > 0:
    print(kai)
    
else:
    print(0)

Solution (Python):
A,B = map(int,input().split())
C = A-2*B
if C <= 0:
  print(0)
else:
  print(C)

Solution (Python):
a,b = map(int,input().split())

if a <= b*2:
  print(0)
else:
  print(a-b*2)

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))

Solution (Python):
values = input()
x = values.split()[0]
y = values.split()[1]

if int(x) <= (2*int(y)):
  print(0)
else:
  print(int(x) - (2*int(y)))

Solution (Python):
print(max(0,eval(input().replace(" ","-2*"))))

Solution (Python):
print(max(0,eval(input().replace(' ','-2*'))))

Solution (Python):
a, b = map(int, input().split())
if a<=b*2:
    print(0)
else:
    print(a-b*2)

Solution (Python):
print(eval('max(0,'+input().replace(' ','-2*')+')'))

Solution (Python):
Window, Cartain = map(int, input().split())

if(Window > Cartain * 2):
    print(Window - Cartain * 2)
else:
    print(0)

Solution (Python):
a,b=map(int,input().split())
if a<2*b:
  print(0)
else:
  print(a-2*b)

Solution (Python):
a,b=map(int,input().split())
print(max(a-2*b,0))

Solution (Python):
A,B=map(int,input().split())
C=A-2*B
if C>0:
    uncovered = C
else:
    uncovered = 0
print(uncovered)

Solution (Python):
input_line = input()
A, B=[int(n) for n in input_line.split(' ')]

r = A-2*B

if r>=0:
  print(r)
else:
  print(0)

Solution (Python):
def solve(a, b):
    return max(0, a - 2*b)
    
a, b = map(int, input().split())
print(solve(a, b))

Solution (Python):
A, B = map(int, input().split())
if A < 2*B:
	print(0)
else:
	print(A-2*B)

Solution (Python):
a,b=map(int, input().split())
if b*2>=a:
  print('0')
else:
  print(a-(b*2))

Solution (Python):
a,b=map(int,input().split())

print(max(0,a-2*b))

Solution (Python):
a,b=map(int,input().split())
k=a-2*b
if k>0:
  print(k)
else:
  print(0)

Solution (Python):
a,b=map(int, input().split())
if a-2*b>0:
  print(a-2*b)
else: 
  print(0)

Solution (Python):
A, B = map(int, input().split())
if B*2 >= A:
  print(0)
else:
  print(A-B*2)

Solution (Python):
a, b = map(int, input().split())
ans = a-b*2
if ans >= 0:
  print(ans)
else:
  print(0)

Solution (Python):
a, b = map(int, input().split())
if b*2 >= a:
    print(0)
else:
    print(a-b*2)

Solution (Python):
a, b = list(map(int, input().split()))
print(max(a-b*2,0))

Solution (Python):
A , B = map(int,input().split())
if A - B*2 < 0:
    print(0)
else:
    print(A-B*2)

Solution (Python):
a, b = map(int, input().split())
res = max(0, a - b*2)
print(res)

Solution (Python):
N,M= (int(i) for i in input().split())
a=N-2*M
print(a if a>0 else 0)

Solution (Python):
a, b = map(int, input().split())
if a - 2*b >= 0:
  print(a-2*b)
else:
  print("0")

Solution (Python):
n,m = map(int,input().split())

print(n-2*m if n-2*m>= 0 else 0)

Solution (Python):
a, b = map(int, input().split())
if a - 2*b >= 0:
    print(a - 2*b)
else:
    print("0")

Solution (Python):
a,b=map(int,input().split())
print(max(0,a-2*b))