Problem:


Score: 100 points

Problem Statement

We have two distinct integers A and B.

Print the integer K such that |A - K| = |B - K|.

If such an integer does not exist, print IMPOSSIBLE instead.

Constraints

All values in input are integers.

0 \leq A,\ B \leq 10^9

A and B are distinct.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the integer K satisfying the condition.

If such an integer does not exist, print IMPOSSIBLE instead.

Sample Input 1

2 16

Sample Output 1

9

|2 - 9| = 7 and |16 - 9| = 7, so 9 satisfies the condition.

Sample Input 2

0 3

Sample Output 2

IMPOSSIBLE

No integer satisfies the condition.

Sample Input 3

998244353 99824435

Sample Output 3

549034394



Sample input:
2 16


Sample output:
9

Submission status: Wrong Answer

Solution code:
A,B=map(int, input().split())
 
if (A+B)%2==0:
	print((A+B)/2)
else:
	print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if (A+B)%2==0:
	print((A+B)/2)
else:
	print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
#ABC135 A

A,B = map(int,input().split())
if (A+B)/2 % 1 == 0:
    print((A+B)/2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (abs(a+b)/2)%2 == 0:
  print((abs(a+b)//2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (abs(a+b)/2)%2 == 0:
  print((abs(a-b)//2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (abs(a-b)/2)%2 == 0:
  print((abs(a-b)//2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int, input().split())
print((a+b)/2 if (a+b)%2==0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
import math

a,b=map(int, input().split())
i=0


if a+b<10**3:
  for k in range((a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
elif a+b>=10**3 and not a+b>=10**6:
  for k in range((10**3)//2,(a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
elif a+b>=10**6 and not a+b>=10**7:
  for k in range((10**6)//2,(a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
elif a+b>=10**7 and not a+b>=10**8:
  for k in range((10**7)//2,(a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
elif a+b>=10**8 and not a+b>=10**9:
  for k in range((10**8)//2,(a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
elif a+b>=10**9 :
  for k in range((10**9)//2,(a+b)//2):
    if a+b==2*k:
      print(k)
      i=1
      break
if i==0:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
print((a**2 - b**2)/(-2*(b-a)))

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
i=a+b/2

if i.is_integer()==True:
    print(i)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
i=a+b/2
print(a)
print(b)
print(i)
if i.is_integer()==True:
    print(i)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if (a+b) % 2 == 0:
    print((a+b)/2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
print((a + b)/ 2 if (a + b) % 2  == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A+B)/2 if (A+B)%2 == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

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

if a+b%2==0:
    print(int((a+b)/2))
else :
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
def main():
    a,b=map(int,(input()).split())
    print((a+b)//2)
main()

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print(A + B // 2 if (A + B) % 2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if a == 0 or b == 0 :
  print('IMPOSSIBLE')
else :
  print(int((a+b)/2))

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if a-b % 2 == 0:
  print((a+b)//2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b= map(int,input().split())
if (b+a)%2==0:
  print((a+b)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b= map(int,input().split())
if (b-a)%2==0:
  print((a+b)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
x = abs(a - b)
if x % 2:
    print('IMPOSSIBLE')
else:
    print(abs(a-(x//2)))

Submission status: Wrong Answer

Solution code:
a, b = [int(n) for n in input().split()]
print(a, b)

if (a+b) % 2 == 0:
    print(int((a+b)/2))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=input().split()
a=int(a)
b=int(b)
if (a+b)%2>=0:
  print(int((a+b)/2))
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if((a+b)/2)==0:
    print((a+b)//2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if (a + b) % 2 ==0:
  print((a+b)/2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
for k in range(1, max(a, b) + 1):
  if k - a == k - b:
    print(k)
    exit()
print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if ((A-B)/2)%1 == 0:
    print(abs((A-B))//2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if a == 0 or b == 0:
    print('IMPOSSIBLE')
else:
    if a > b:
        print(a-abs(a-b)//2)
    else:
        print(b-abs(a-b)//2)

Submission status: Wrong Answer

Solution code:

def main():
    a, b = map(int, input().split())
    if ((a + b) // 2 ) % 2 == 0:
        print((a + b) // 2)
    else:
        print('IMPOSSIBLE')


if __name__ == "__main__":
    main()

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
ans = (A+B)/2
print(int(ans)) if ans % 2 == 0 else print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
N,M=map(int,input().split())
if (N+M)%2==0:
  print((N+M)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
#k = int(input())
#s = input()
#a, b = map(int, input().split())
#s, t = map(str, input().split())

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

if (a+b)%2 != 0:
    print("INPOSSIBLE")
else:
    print((a+b)//2)

Submission status: Wrong Answer

Solution code:
#k = int(input())
#s = input()
#a, b = map(int, input().split())
#s, t = map(str, input().split())

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

if (a+b)%2 != 0:
    print("INPOSIBLE")
else:
    print((a+b)//2)

Submission status: Wrong Answer

Solution code:
a,b=list(map(int,input().split()))
if abs(int((a-b)/2))==abs(int((b-a)/2)):
  print(int((a+b)/2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
print((a+b)//2 if (a+b)%2==0 else 'INPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = [int(i) for i in input().split(" ")]
print("IMPOSSIBLE" if (a+b)%2 else (a+b)/2)

Submission status: Wrong Answer

Solution code:
# -*- coding: utf-8 -*-

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

print((a+b)/2 if (a+b)%2==0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
# -*- coding: utf-8 -*-

def main():

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

    if (A + B) % 2 == 0:
        ans = (A + B) / 2

    else:
        ans = 'IMPOSSIBLE'

    print(ans)


if __name__ == "__main__":
    main()

Submission status: Wrong Answer

Solution code:
import sys
a,b=map(int, input().split())
for i in range(10**10):
    if abs(a-i)==abs(b-i):
        print(i)
        sys.exit()
    else:
        print('IMPOSSIBLE')
        sys.exit()

Submission status: Wrong Answer

Solution code:
import sys
a,b=map(int, input().split())
for i in range(10**5):
    if abs(a-i)==abs(b-i):
        print(i)
        sys.exit()

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==0:
    print((a+b)/2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (b-a)%2==0:
  print(int((b-a)/2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (b-a)%2==0:
  print((b-a)/2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
x = (a-b)%2
print(abs((a-b)/2-a) if x == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
n=a+b
if n%2==0:print(n/2)
else:print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
K=(A+B)/2
if(K.is_integer()==True):
  print(K)
else:
  print("Impossible")

Submission status: Wrong Answer

Solution code:
n=input().split()
A=int(n[0])
B=int(n[1])
K=int((A+B)/2)
if abs(A-K)==abs(B-K):
    print(K)
else:
    print("imppsible")

Submission status: Wrong Answer

Solution code:
import sys
A,B = map(int,input().split())

if not ( 0 <= A <= 10**9 and 0 <= B <= 10**9 ): sys.exit()

if A % 2 != B % 2:
    print('IMPOSSIBLE')
    sys.exit()
else:
    print((A+B)/2)

Submission status: Wrong Answer

Solution code:
a, b = map(int,input().split())
x = a + b
if x % 2 == 0:
    print(x / 2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
if abs(A - B) % 2 == 1:
    print('IMPOSSIBLE')
else:
    print((A + B) / 2)

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
k = a+b
if k%2:
    print('INPOSSIBLE')
else:
    print(k//2)

Submission status: Wrong Answer

Solution code:
def main():
 a,b = map(int,input().split())
 if abs(a - b) % 2 == 0:
     print(abs(a - b) // 2)
 else:
     print('IMPOSSIBLE')
main()

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a-b)%2==1:
  print('IMPOSSIBLE')
else:
  print(abs(a-b)//2)

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
if((a+b)%2==0):
  print(int((a+b)/2))
else:
  print("IMPOSSIBE")

Submission status: Wrong Answer

Solution code:
a, x =map(int, input().split())
if (a+x)%2 ==0:
  print((a+x)/2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if abs(a-b)%2==0:
  print(abs(abs(a-b)//2-a))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if abs(a-b)%2==0:
  print(abs(a-b)//2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

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

if a+b%2 == 0:
  print(int((a+b)/2))
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if a - b % 2 == 1:
    print('IMPOSSIBLE')
else:
    dif = abs(a - b) // 2
    if a < b:
        print(a + dif)
    else:
        print(b + dif)

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if a - b % 2 == 1:
    print('IMPOSSIBLE')
else:
    dif = (a - b) // 2
    if a < b:
        print(a + dif)
    else:
        print(b + dif)

Submission status: Wrong Answer

Solution code:
A,B = map(int, input().split())
if A+B%2 == 1:
  print('IMPOSSIBLE')
else:
  print((A+B)//2)

Submission status: Wrong Answer

Solution code:
A,B = map(int, input().split())
if A+B%2 == 1:
  print('IMPOSSIBLE')
else:
  print(A+B//2)

Submission status: Wrong Answer

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

if a % 2 == 0 and b % 2 == 0:
  print(int((a+b)/2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int,input().split())
if (a - b) % 2 == 0:
  print(a-(a-b)%2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int,input().split())
if (a - b) % 2 == 0:
  print(a+(a-b)%2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
print((a+b)/2 if (a+b)%2==0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
print((a+b)/2) if ((a+b)%2 == 0)&(a!=0)&(b!=0) else print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
print((a+b)/2) if (a+b)%2 == 0 else print("IMPOSSIBLE")

Submission status: Wrong Answer

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

ans = ''
if a % 2 != b % 2:
    ans = 'INPOSSIBLE'
else:
    ans = (a + b) // 2
print(ans)

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
x = (a+b)/2
if x%2 == 0:
    print(int(x))
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

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

for i in range(1000000):
    re1 = abs(a - i)
    re2 = abs(b - i)
    if re1 == re2:
        print(i)
        exit(0)

print("IMPOSSIBLE")

Submission status: Wrong Answer

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

for i in range(100000):
    re1 = abs(a - i)
    re2 = abs(b - i)
    if re1 == re2:
        print(i)
        exit(0)

print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if (a + b) % 2 == 0 :
  print ((a + b) / 2)
else :
  print ("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
def main():
    a, b = map(int, input().split())
    if a % 2 and b % 2:
        print((a+b)/2)
    else:
        print('IMPOSSIBLE')
main()

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if a + b % 2 == 1: 
    print('IMPOSSIBLE')
    exit()
print((a+b) // 2)

Submission status: Wrong Answer

Solution code:
# Sol : (n1 + n2)/2
# Ex : 
# Q : 16 - x = 2 - x
# => 16 + x = 2 + x
# => 16 + 2 = 2x
# => 18/2 = x
# +> 9 = x
a = list(map(int, input().split()))
if ((a[0] + a[1]) // 2) * 2 != a[0] + a[1]:
    print("Impossible")
else:
    print(((a[0] + a[1]) // 2))

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A+B) // 2 if (A+B) % 2 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
print((lambda x:('IMPOSSIBLE' if (x[0]+x[1])%2==1 else (x[0]+x[1])/2))(list(map(int,input().split()))))

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (a+b) % 2 == 0:
  print(int((a+b)/2))
else:
  print("impossible")

Submission status: Wrong Answer

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

for i in range(a,b):
  if abs(a-i) == abs(b-i):
    print(i)
    exit()
print("impossible")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if abs(a-b)==1:
    print("IMPOSSIBLE")
else:
    print(int((a+b)/2))

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if a%2==0 and b%2==0:
  print((a+b)//2)
  
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
print((a+b)//2 if (a+b)/2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if a%2==b%2:
    print((a+b)/2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
print((a+b)//2)

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (a+b)%2 == 0:
    print((a+b//2))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
print((A+B)/2) if (A+B)%2==0 else print('IMPOSSIBLE')

Submission status: Wrong Answer

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

if (A+B)&2 == 0:
  print((A+B)//2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if a+b % 2 == 1:
    print("IMPOSSIBLE")
else:
     print(int((a+b)/2))

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if a+b % 2 == 1:
    print("IMPOSSIBLE")
else:
    print((a+b)//2)

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if a+b % 2 == 1:
    print("IMPOSSIBLE")
else:
    print((a+b)/2)

Submission status: Wrong Answer

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

if (b-a)%2==0:
    print(int((b-a)/2))
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==0:
  print((a+b)/2)
  
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==0:
  print((a+b)/2)
  
else:
  print('impossible')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
ans = (a+b)/2

if ans == int(ans):
  print(ans)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if a % 2 != b % 2:
	print('IMPOSSIBLE')
else:
	print((a + b) / 2)

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
if a+b % 2 == 0:
  print((a+b) // 2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split());print((a+b)//2 if (a+b)%2==0 else 'IMPSSIBLE')

Submission status: Wrong Answer

Solution code:
def harmony(a, b):

    return "IMPOSSIBLE" if abs(a-b)%2 != 0 else int(abs(a-b)//2)
def main():
    a, b = map(int, input().split())
    print(harmony(a, b))

if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if((a + b) % 2 == 0):
    print((a + b) / 2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if (a + b) % 2 == 1:
    print('INPOSSIBLE')
else:
    print((a + b) // 2)

Submission status: Wrong Answer

Solution code:
import sys
A, B = map(int, input().split())
tmp = 0

if (abs(A)-abs(B))%2 == 1:
  print("IMPOSSIBLE")
  sys.exit()

if A < B:
  tmp = A
  A = B
  B = tmp

if A > 0 and B > 0:
  K = (A+B)/2
elif A < 0 and B < 0:
  K = -(abs(A)+abs(B))/2
else:
  K = A-(abs(A)+abs(B))/2

print(K)

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if abs(a-b)%2==0:
  print(int(abs(a-b)/2))
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
import sys
import math
import bisect

def main():
    a, b = map(int, input().split())
    if abs(a - b) % 2 == 0:
        k = abs(a - b) // 2
        print(k)
    else:
        print('IMPOSSIBLE')
    
if __name__ == "__main__":
    main()

Submission status: Wrong Answer

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

ans = abs(a - b) / 2

if ans.is_integer():
    print(int(ans+a))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B = map(int, input().split())
# R = int(input())
# B = int(input())
# C = int(input())
# b = input()
print((A + B) / 2 if (A + B) % 2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print("(A+B)//2" if (A+B)%2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print("(A+B)/2" if (A+B)%2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
if A%2==B%2: print('IMPOSSIBLE')
else: print(int((A+B)/2))

Submission status: Wrong Answer

Solution code:
from collections import defaultdict, deque, Counter
from heapq import heappush, heappop, heapify
from itertools import permutations, accumulate, combinations, combinations_with_replacement
from math import sqrt, ceil, floor, factorial
from bisect import bisect_left, bisect_right
from copy import deepcopy
from operator import itemgetter
from functools import reduce
#from fractions import gcd
#from math import gcd
import sys
def I(): return int(input())
def Is(): return map(int, input().split())
def LI(): return list(map(int, input().split()))
def TI(): return tuple(map(int, input().split()))
def IR(n): return [I() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def TIR(n): return [TI() for _ in range(n)]
def S(): return input()
def Ss(): return input().split()
def LS(): return list(input())
def SR(n): return [S() for _ in range(n)]
def SsR(n): return [Ss() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
sys.setrecursionlimit(10**6)
MOD = 10**9+7
INF = float('inf')


a, b = Is()

if a+b % 2 == 1:
    print("IMPOSSIBLE")
else:
    print(int((a+b)//2))

Submission status: Wrong Answer

Solution code:
from collections import defaultdict, deque, Counter
from heapq import heappush, heappop, heapify
from itertools import permutations, accumulate, combinations, combinations_with_replacement
from math import sqrt, ceil, floor, factorial
from bisect import bisect_left, bisect_right
from copy import deepcopy
from operator import itemgetter
from functools import reduce
#from fractions import gcd
#from math import gcd
import sys
def I(): return int(input())
def Is(): return map(int, input().split())
def LI(): return list(map(int, input().split()))
def TI(): return tuple(map(int, input().split()))
def IR(n): return [I() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def TIR(n): return [TI() for _ in range(n)]
def S(): return input()
def Ss(): return input().split()
def LS(): return list(input())
def SR(n): return [S() for _ in range(n)]
def SsR(n): return [Ss() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
sys.setrecursionlimit(10**6)
MOD = 10**9+7
INF = float('inf')


a, b = Is()

if a+b % 2 == 1:
    print("IMPOSSIBLE")
else:
    print(int((a+b)/2))

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
div, rem = divmod(abs(A - B), 2)
print("IMPOSSIBLE" if rem else abs(A - div))

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A+B)//2) if (A-B)%2 !=0 else print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A+B)/2 if (A+B) % 2 == 0 else "IMPOSSIBLE")

Submission status: Wrong Answer

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

if (a+b)%2 == 0:
  print((a+b)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B = map(int, input().split())
print((A+B)/2 if (A+B)%2 == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A,B = map(int, input().split())
print((A+B)/2 if (A+B)/2%2 == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (abs(b-a))%2==0:
    print(abs((b-(b-a)/2)))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
if (b-a)%2==0:
    print((b-(b-a)/2))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
if A%2 != B%2:
    print('IMPOSSIBLE')
else:
    print((A+B)/2)

Submission status: Wrong Answer

Solution code:
a , b = map(int, input().split())
x = a-b
if x%2 == 1:
    print("IMPOSSIBLE")
else:
    print((a+b)/2)

Submission status: Wrong Answer

Solution code:
import math 
a,b=(int(x) for x in input().split())
print(a)
print(b)
if(a%2 != b%2):
    print("IMPOSSIBLE")
else:
    k=int (a+b)/2
    print(math.floor(k))

Submission status: Wrong Answer

Solution code:
# ABC 135
A,B =map(int,input().split())
if A//2==0 and B//2==0:
    print(abs(A-B)//2)
elif A//2!=0 and B//2!=0:
    print(abs(A+B)//2)
else:
    print("IMPOSSIBLE ")

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
if A+B % 2 !=0:
    print("IMPOSSIBLE")
else:print((A+B)//2)

Submission status: Wrong Answer

Solution code:
import math
a,b=map(int,input().split())

ans = abs(a-b)
M = max(a,b)

if ans%2==0:
    ans/=2
    print(M-ans)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
c = a+b
if c%2==0:
    print((a+b)/2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
k=(a+b)/2
if int(k)==k:
  print(k)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
k=(a+b)/2
if k.is_integer():
  print(k)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B= map(int, input().split())
diff_ba = B-A
if diff_ba % 2 == 0:
  print(A + diff_ba)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int,input().split())
f=True
if a%2==0 and b%2==0:
  print((a+b)//2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==0:
    print(abs((a-b)/2)+min(a,b))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
for i in range(int((a+b)/2)-5, int((a+b)/2)+5):
  if abs(a-i) == abs(b-i):
    print(i)
  else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if a%2==1 or b%2==1:
  print("impossible")
  exit()
else:
  print((a+b)//2)

Submission status: Wrong Answer

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

if a%2==1 or b%2==1:
  print("impossible")
  exit()
else:
  print((a+b)/2)

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a-b)&1:print("IMPOSSIBLE")
else:print("POSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = list(map(int,input().split()))
print(int((A+B)/2))

Submission status: Wrong Answer

Solution code:
a, b = list(map(int, input().split()))
m = max(a, b) - min(a, b)
if m % 2 == 0:
    print(int(m/2))
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
ans = -(a*a-b*b)/(2*(b-a))
if type(ans) == int:
    print(ans)

else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
q, r = divmod(sum(map(int, input().split())), 2)
print(q if r else 'IMPOSSIBLE')

Submission status: Wrong Answer

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

if (a+b)%2==0:
    print((a+b)/2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if (a+b)%2==0:
    print((a+b)%2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
#--Harmony

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

if (N % 2 == 0):
  print(N/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if a+b % 2 ==0:
  print(int((a+b)/2))
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==1:
    print("IMPOSSIBLE")
else:
    print((a+b)/2)

Submission status: Wrong Answer

Solution code:
import numpy as np
def main():
    a, b = map(int, input().split())
    for k in range(min(a,b), max(a,b)+1):
        ak = np.abs( a - k )
        bk = np.abs( b - k )
        if ak == bk:
            print(( a + b ) / 2)
            exit(0)
    print("IMPOSSIBLE")

if __name__ == "__main__":
    main()

Submission status: Wrong Answer

Solution code:
def main():
    a, b = map(int, input().split())
    if a == 0 or b == 0: print("IMPOSSIBLE")
    else:print( int((a + b) / 2))

if __name__ == "__main__":
    main()

Submission status: Wrong Answer

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

if (A-B)%2 != 0:
  print('IMPOEEIBLE')
else:
  print(abs(A-B)//2)

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
ans = (A+B)/2

if ans == (A+B)//2:
  print(ans)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
if (a%2 == 0 and b%2 == 0) or (a%2 != 0 and b%2 != 2):
  print((a+b)//2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

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

if A % 2 != B % 2:
  K = "IMPOSSIBLE"
elif A > B:
  # A - K = - (B - K)
  # 2K = A + B
  K = int((A + B) / 2)
else:
  # B - K = - (A - K)
  # 2K = B - A
  K = int((B - A) / 2)
print(K)

Submission status: Wrong Answer

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

if A % 2 != B % 2:
  print("IMPOSSIBLE")
elif A >= B:
  print(A - int((A + B) / 2))
else:
  print(B - int((A + B) / 2))

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
if (a+b)%2==0:
    print((a+b)/2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
print((a+b)/2)

Submission status: Wrong Answer

Solution code:
a  = list(map(int, input().split()))
b = abs(a[0] - a[1])

if b % 2 == 0:
  print(abs(a[0] - b // 2))
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
if (b-a) % 2 == 0:
    print((a+b) / 2)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
print(abs(int((A-B)/2)) if (A-B)%2==0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int, input().split())
if (a-b)%2==0:
  print((a+b)/2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

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

if abs(a-b)//2 == abs(a-b)/2:
  print(int(abs(a-b)/2))
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:

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

if ((a+b)/2) % 1 == 0:
    print((a+b)/2)
else:
    "IMPOSSIBLE"

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
K = (A+B)/2
judge = isinstance(K, float)
if judge:
  print("IMPOSSIBLE")
else:
  print((A+B)//2)

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
K = (A+B)//2
judge = isinstance(K, float)
if judge:
  print("IMPOSSIBLE")
else:
  print(K)

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
K = (A+B)/2
judge = isinstance(K, float)
if judge:
  print("IMPOSSIBLE")
else:
  print(K)

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
K = (A+B)/2
judge = isinstance(K, float)
if judge:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A + B) / 2 if (A + B) % 2 == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A, B = map(int, input().split())
print((A + B) / 2 if A + B % 2 == 0 else 'IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
if (A+B)%2==0:
    print(A+B//2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a , b = list(map(int,input().split()))
if (a-b)%2 == 1:
  print("IMPOSSIBLE")
else:
  print((a-b)//2)

Submission status: Wrong Answer

Solution code:
A= list(map(int,input().split()))
if (A[0]+A[1])%2 == 0:
    print((A[0]+A[1])/2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A ,B = list(map(int,input().split()))
if (A+B)%2==0:
    print((A+B)/2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A= list(map(int,input().split()))
if (A[0]+A[1])//2 == 0:
    print(abs(A[0]-(A[0]+A[1])/2))
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A= list(map(int,input().split()))
if (A[0]+A[1])//2 == 0:
    print((A[0]+A[1])/2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A= list(map(int,input().split()))
if (A[0]+A[1])//2 == 0:
    print((A[0]+A[1]))
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A= list(map(int,input().split()))
if (A[0]+A[1])//2 == 0:
    print((A[0]+A[1])//2)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

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

if (a+b)%2 == 0 :
    print((a+b)/2)
else :
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if (a+b)%2 == 0 :
    print(a+b/2)
else :
    print("IMPOSSIBLE")