Problem p02640 (python)

Fixed submission:
# template by 3xC and starkizard.
# contributors: 

#####################################################################################
from __future__ import division, print_function 

import sys
import os
from collections import Counter, deque, defaultdict
import itertools
import math
import io


"""Uncomment modules according to your need"""


# from bisect import bisect_left, bisect_right, insort
# from heapq import heappop, heapify, heappush
# from random import randint as rn
# from Queue import Queue as Q
# from copy import deepcopy
# from decimal import *
# import re
# import operator

#####################################################################################
# this enables you to write python3 code with PyPy2 (Python 2)
if sys.version_info[0] < 3:
    input = raw_input
    range = xrange

    filter = itertools.ifilter
    map = itertools.imap
    zip = itertools.izip

#####################################################################################

"""value of mod"""
MOD = 998244353
mod = 10**9 + 7

"""Uncomment next 4 lines if doing huge recursion"""
# import threading
# threading.stack_size(1<<27)
# sys.setrecursionlimit(10000

def prepare_factorial(mod=mod):
    """ returns two lists, factorial and inverse factorial modulo argument by default 10**9 +7 """
    # Comment code out when you don't need inverse factorial or vice versa
    fact = [1]
    for i in range(1, 200005):
        fact.append((fact[-1] * i) % mod)

    ifact = [0] * 200005
    ifact[200004] = pow(fact[200004], mod - 2, mod)
    for i in range(200004, 0, -1):
        ifact[i - 1] = (i * ifact[i]) % mod

    return fact, ifact

def modinv(n, p):
    """ returns N inverse modulo p """
    return pow(n, p - 2, p)

def ncr(n, r,  fact, ifact):
    """ takes 4 arguments: n , r and factorial and inverse factorial lists"""
    t = (fact[n] * (ifact[r]*ifact[n-r]) % MOD)% MOD
    return t


def get_n(Sum):    
    """this function returns the maximum n for which Summation(n) <= Sum"""
    ans = (-1 + sqrt(1 + 8*Sum))//2
    return ans

def sieve(n):
    """ returns a list of prime numbers till n """
    if n < 2: return list()
    prime = [True for _ in range(n + 1)]
    p = 3
    while p * p <= n:
        if prime[p]:
            for i in range(p * 2, n + 1, p):
                prime[i] = False
        p += 2
    r = [2]
    for p in range(3, n + 1, 2):
        if prime[p]:
            r.append(p)
    return r



def divs(n, start=1):
    """ returns a list of all divisors till n """
    divisors = []
    for i in range(start, int(math.sqrt(n) + 1)):
        if n % i == 0:
            if n / i == i:
                divisors.append(i)
            else:
                divisors.extend([i, n // i])
    return divisors



def divn(n, primes):
    """ returns the number of divisors, two arguments n and the sieve till n """
    divs_number = 1
    for i in primes:
        if n == 1:
            return divs_number
        t = 1
        while n % i == 0:
            t += 1
            n //= i
        divs_number *= t



def lrfind(d, x, default=-1):
    """ Takes 2 arguments an iterable and an element. returns a tuple (firstoccurence,lastoccurence) -1 if not found """
    left = right = -1
    for i in range(len(d)):
        if d[i] == x:
            if left == -1: left = i
            right = i
    if left == -1:
        return default, default
    else:
        return left, right

def gcd(x, y): # math.gcd is slower
    """ returns greatest common divisor of x and y """
    while y:
        x, y = y, x % y
    return x

def check_sorted(a):
    ''' returns True/False '''
    for i in range(len(a)-1):
        if a[i]>a[i+1]:
            return False
    return True
def ceil(n, k=1): return n // k + (n % k != 0) #returns math.ceil but protecting against floating inconsistencies
def input(): return sys.stdin.readline().strip()
def ii(): return int(input()) #inputs integer
def mi(): return map(int, input().split()) # inputting space seperated variables for example x,y,z
def li(): return list(map(int, input().split())) #inputting a space seperated list of integers
def lw(): return input().split() #inputting a space seperated list of strings
def lcm(a, b): return abs(a * b) // gcd(a, b) #returns LCM of two arguments
def prr(a, sep=' ', end='\n'): print(sep.join(map(str, a)), end=end) #For printing an iterable with seperator sep as optional second argument (default : " "), ending character (default: "\n") as optional third
def dd(): return defaultdict(int) #returns a dictionary with values defaulted to 0
def ddl(): return defaultdict(list) #returns a dictionary with values defaulted to []
def write(s): return sys.stdout.write(s)












###################################################################
def main():
    #CODE GOES HERE:
    x,y=mi()
    if (y%2!=0):
        print("No")
        return
    if (y//2<x):
        print("No")
        return
    if (y/2==x):
        print("Yes")
        return
    
    if(y/4 >x):
        print("No")
        return

    if(y/4==x):
        print("Yes")
        return
    print("Yes")

        











































""" -------- Python 2 and 3 footer by Pajenegod and c1729 ---------"""

py2 = round(0.5)
if py2:
    from future_builtins import ascii, filter, hex, map, oct, zip
    range = xrange

import os, sys
from io import IOBase, BytesIO

BUFSIZE = 8192

class FastIO(BytesIO):
    newlines = 0

    def __init__(self, file):
        self._file = file
        self._fd = file.fileno()
        self.writable = "x" in file.mode or "w" in file.mode
        self.write = super(FastIO, self).write if self.writable else None

    def _fill(self):
        s = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
        self.seek((self.tell(), self.seek(0, 2), super(FastIO, self).write(s))[0])
        return s

    def read(self):
        while self._fill(): pass
        return super(FastIO, self).read()

    def readline(self):
        while self.newlines == 0:
            s = self._fill();
            self.newlines = s.count(b"\n") + (not s)
        self.newlines -= 1
        return super(FastIO, self).readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.getvalue())
            self.truncate(0), self.seek(0)


class IOWrapper(IOBase):

    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        if py2:
            self.write = self.buffer.write
            self.read = self.buffer.read
            self.readline = self.buffer.readline
        else:
            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')


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip('\r\n')
# sys.stdin = open('input.txt', 'r')
# sys.stdout = open('output.txt', 'w')

""" main function"""

if __name__ == '__main__':
    main()
    # threading.Thread(target=main).start()

Buggy submission (verdict: Runtime Error):
    # template by 3xC and starkizard.
    # contributors: 

    #####################################################################################
    from __future__ import division, print_function 

    import sys
    import os
    from collections import Counter, deque, defaultdict
    import itertools
    import math
    import io


    """Uncomment modules according to your need"""


    # from bisect import bisect_left, bisect_right, insort
    # from heapq import heappop, heapify, heappush
    # from random import randint as rn
    # from Queue import Queue as Q
    # from copy import deepcopy
    # from decimal import *
    # import re
    # import operator

    #####################################################################################
    # this enables you to write python3 code with PyPy2 (Python 2)
    if sys.version_info[0] < 3:
        input = raw_input
        range = xrange

        filter = itertools.ifilter
        map = itertools.imap
        zip = itertools.izip

    #####################################################################################

    """value of mod"""
    MOD = 998244353
    mod = 10**9 + 7

    """Uncomment next 4 lines if doing huge recursion"""
    # import threading
    # threading.stack_size(1<<27)
    # sys.setrecursionlimit(10000

    def prepare_factorial(mod=mod):
        """ returns two lists, factorial and inverse factorial modulo argument by default 10**9 +7 """
        # Comment code out when you don't need inverse factorial or vice versa
        fact = [1]
        for i in range(1, 200005):
            fact.append((fact[-1] * i) % mod)

        ifact = [0] * 200005
        ifact[200004] = pow(fact[200004], mod - 2, mod)
        for i in range(200004, 0, -1):
            ifact[i - 1] = (i * ifact[i]) % mod

        return fact, ifact

    def modinv(n, p):
        """ returns N inverse modulo p """
        return pow(n, p - 2, p)

    def ncr(n, r,  fact, ifact):
        """ takes 4 arguments: n , r and factorial and inverse factorial lists"""
        t = (fact[n] * (ifact[r]*ifact[n-r]) % MOD)% MOD
        return t


    def get_n(Sum):    
        """this function returns the maximum n for which Summation(n) <= Sum"""
        ans = (-1 + sqrt(1 + 8*Sum))//2
        return ans

    def sieve(n):
        """ returns a list of prime numbers till n """
        if n < 2: return list()
        prime = [True for _ in range(n + 1)]
        p = 3
        while p * p <= n:
            if prime[p]:
                for i in range(p * 2, n + 1, p):
                    prime[i] = False
            p += 2
        r = [2]
        for p in range(3, n + 1, 2):
            if prime[p]:
                r.append(p)
        return r



    def divs(n, start=1):
        """ returns a list of all divisors till n """
        divisors = []
        for i in range(start, int(math.sqrt(n) + 1)):
            if n % i == 0:
                if n / i == i:
                    divisors.append(i)
                else:
                    divisors.extend([i, n // i])
        return divisors



    def divn(n, primes):
        """ returns the number of divisors, two arguments n and the sieve till n """
        divs_number = 1
        for i in primes:
            if n == 1:
                return divs_number
            t = 1
            while n % i == 0:
                t += 1
                n //= i
            divs_number *= t



    def lrfind(d, x, default=-1):
        """ Takes 2 arguments an iterable and an element. returns a tuple (firstoccurence,lastoccurence) -1 if not found """
        left = right = -1
        for i in range(len(d)):
            if d[i] == x:
                if left == -1: left = i
                right = i
        if left == -1:
            return default, default
        else:
            return left, right

    def gcd(x, y): # math.gcd is slower
        """ returns greatest common divisor of x and y """
        while y:
            x, y = y, x % y
        return x

    def check_sorted(a):
        ''' returns True/False '''
        for i in range(len(a)-1):
            if a[i]>a[i+1]:
                return False
        return True
    def ceil(n, k=1): return n // k + (n % k != 0) #returns math.ceil but protecting against floating inconsistencies
    def input(): return sys.stdin.readline().strip()
    def ii(): return int(input()) #inputs integer
    def mi(): return map(int, input().split()) # inputting space seperated variables for example x,y,z
    def li(): return list(map(int, input().split())) #inputting a space seperated list of integers
    def lw(): return input().split() #inputting a space seperated list of strings
    def lcm(a, b): return abs(a * b) // gcd(a, b) #returns LCM of two arguments
    def prr(a, sep=' ', end='\n'): print(sep.join(map(str, a)), end=end) #For printing an iterable with seperator sep as optional second argument (default : " "), ending character (default: "\n") as optional third
    def dd(): return defaultdict(int) #returns a dictionary with values defaulted to 0
    def ddl(): return defaultdict(list) #returns a dictionary with values defaulted to []
    def write(s): return sys.stdout.write(s)












    ###################################################################
    def main():
        #CODE GOES HERE:
        x,y=mi()
        if (y//2<x):
            print("No")
            return
        if (y/2==x):
            print("Yes")
            return
        
        if(y/4 >x):
            print("No")
            return

        if(y/4==x):
            print("Yes")
            return
        
        print("Yes")

            











































    """ -------- Python 2 and 3 footer by Pajenegod and c1729 ---------"""

    py2 = round(0.5)
    if py2:
        from future_builtins import ascii, filter, hex, map, oct, zip
        range = xrange

    import os, sys
    from io import IOBase, BytesIO

    BUFSIZE = 8192

    class FastIO(BytesIO):
        newlines = 0

        def __init__(self, file):
            self._file = file
            self._fd = file.fileno()
            self.writable = "x" in file.mode or "w" in file.mode
            self.write = super(FastIO, self).write if self.writable else None

        def _fill(self):
            s = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.seek((self.tell(), self.seek(0, 2), super(FastIO, self).write(s))[0])
            return s

        def read(self):
            while self._fill(): pass
            return super(FastIO, self).read()

        def readline(self):
            while self.newlines == 0:
                s = self._fill();
                self.newlines = s.count(b"\n") + (not s)
            self.newlines -= 1
            return super(FastIO, self).readline()

        def flush(self):
            if self.writable:
                os.write(self._fd, self.getvalue())
                self.truncate(0), self.seek(0)


    class IOWrapper(IOBase):

        def __init__(self, file):
            self.buffer = FastIO(file)
            self.flush = self.buffer.flush
            self.writable = self.buffer.writable
            if py2:
                self.write = self.buffer.write
                self.read = self.buffer.read
                self.readline = self.buffer.readline
            else:
                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')


    sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
    input = lambda: sys.stdin.readline().rstrip('\r\n')
    # sys.stdin = open('input.txt', 'r')
    # sys.stdout = open('output.txt', 'w')

    """ main function"""

    if __name__ == '__main__':
        main()
        # threading.Thread(target=main).start()