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

Submission status: Wrong Answer

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

k = abs(a - b)
if k % 2 == 0:
  print(max(abs(a-k/2),abs(b-k/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:
n , m = map(int, input().split())
flg_IMPOSSIBLE = 0

if n == 0 or m == 0:
    flg_IMPOSSIBLE = 1

if (n + m % 2) == 1:
    flg_IMPOSSIBLE = 1
    
if flg_IMPOSSIBLE == 1:
    print("IMPOSSIBLE")
else:
    print((n + m) // 2)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

k = (a+b)/2

if abs(a-k) == abs(b-k):
    print(int(k))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

k = (a+b)/2

if abs(a-k) == abs(b-k):
    print(k)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:

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

answer = 0
K= (A+B)/2

if A!= B and (A+B)%2 == 0 and (A-K)*(B-K)<0:
	print(int(K))
else:
  	print("Impossible")

Submission status: Wrong Answer

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

k = (A + B) / 2

answer = 0
if A - k >= 0 and -B + k >=0 :
	answer = 1
    
elif -A + k >=0 and B - k >= 0 :
	answer = 1 
    
if answer == 1 and (A + B) % 2 == 0  :
	print(k)
else :
	print("IMPOSSIBLE")

Submission status: Wrong Answer

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

k = (A + B) / 2

answer = 0
if A - k >= 0 and -B + k <=0 :
	answer = 1
    
elif -A + k <=0 and B - k >= 0 :
	answer = 1 
    
if answer == 1 and (A + B) % 2 == 0  :
	print(k)
else :
	print("IMPOSSIBLE")

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
import sys
import os


def main():
    if os.getenv("LOCAL"):
        sys.stdin = open("input.txt", "r")

    A, B = list(map(int, sys.stdin.buffer.readline().split()))
    print(int(abs(A-(abs(A-B))/2)) if (abs(A-B))%2 == 0 else 'IMPOSSIBLE')


if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
import sys
import os


def main():
    if os.getenv("LOCAL"):
        sys.stdin = open("input.txt", "r")

    A, B = list(map(int, sys.stdin.buffer.readline().split()))
    print((abs(A-B))//2 if (abs(A-B))%2 == 0 else 'IMPOSSIBLE')


if __name__ == '__main__':
    main()

Submission status: Wrong Answer

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

for i in range(a,b+1):
    if abs(a-i) == abs(b-i):
        print(i)
        flg = False
        break

if flg:
    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(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())

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 i in range(A, B):
    if abs(A-i) == abs(B-i):
        print(i)
        break
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%3 != 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('IMPOSSIBLE')
else:
  print((a+abs(b))/2)

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:
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((a+b)/2)

Submission status: Wrong Answer

Solution code:
A , B = (map(int , input().split()))
asn = (A + B) /2
if asn.is_integer() == True:
    print(asn)
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())
ans = (a+b)/2
if ans%1==0:
  print(ans)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
l=max(a-b,b-a)
print(min(a,b)+l)

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 = [int(x) for x in input().split(" ")]

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

Submission status: Wrong Answer

Solution code:
A, B = [int(x) for x in input().split(" ")]

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

Submission status: Wrong Answer

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

if (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(-1)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
A,B=map(int,input().split())
K=(A+B)/2
Kint=int(K)
if (K==Kint):
  print (K)
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:
    x = (a + b)/2
    print(x)
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((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())

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
A, B = map(int,input().split())
 
if (A+B) % 2 == 1:
  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())

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

Submission status: Wrong Answer

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

i = (A+B)/2 

if i % 1 ==0:
    print(i)
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

Solution code:
A,B = (int(x) for x in input().split())

if (A+B) % 2 == 0:
    print(int((A+B)/2))
else:
    print('IMPOSSIBLIE')

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('IMPPOSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

n = abs(a-b)
print("IMPOSSIBLE" if n&1 else (a+b)/2)

Submission status: Wrong Answer

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

n = abs(a-b)
print("IMPOSSIBLE" if n&1 else n)

Submission status: Wrong Answer

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

n = abs(a-b)
print(n if n&1 else "IMPOSSIBLE")

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
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 (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 (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) // 1 == 1:
  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(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 = map(int,input().split())

if (A+B)%2 != 0:
    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)

Submission status: Wrong Answer

Solution code:
a,b = map(int, input().split())
if a == b:
  print(0)
elif (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 = (int(i) for i in 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())
K = A + B
if K % 2 == 0:
    print(K)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

if add % 2 == 0:
	result = int(add / 2)
	print(result)
	abs_result = abs(A - result)
	print('|{}-{}| = {} and |{}-{}| = {}, so {} satisfies the condition.'.format(A, result, abs_result, B, result, abs_result, result))
else:
	print('IMPOSSIBLE')
	print('No integer satiesfies the condition.')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

c = max(a,b)-min(a,b)
if c % 2 == 0:
  print("c // 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, B = list(map(int, input().split()))
result = (A+B)/2 if (A+B)%2 == 0 else "IMPOSSIBLE"
print(result)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

if (B-A) % 2 == 1:
    print('impossible')
    exit()

tmp = (B-A) // 2
print(B-tmp)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
x=(a+b)/2
if x.is_integer()==1:print(x)
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:
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())


if (a + b) % 2 == 0:
    k = (a + b) / 2
    print(k)
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())
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="IMPOSSIBLE"
if a%b==0 or b%a==0:
	ans=(a+b)//2
print(ans)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
import sys

num = list(map(int,input().split()))
A = num[0]
B = num[1]

if A%2==0 and B%2==0:
	print((A+B)/2)
	sys.exit()
if A%2==1 and B%2==1:
	print((A+B)/2)
	sys.exit()
print("IMPOSSIBLE" )

Submission status: Wrong Answer

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

k =(a+b)/2

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

Submission status: Wrong Answer

Solution code:
a, b = map(int, input().split())
for k in range(a, b+1):
    if abs(a-k) == abs(b-k):
        print(k)
        exit(0)
print('IMPOSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
A,B=map(int, input().split())
if (A+B)%2 == 0:
  K=(A+B)/2
  print(K)
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:
a, b = map(int, input().split())

if a == b or ((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 ==0:
  print(k/2)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

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

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

else:
    print("IMPOSSIBE")

Submission status: Wrong Answer

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

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

else:
    print("IMPOSSIBE")

Submission status: Wrong Answer

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

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

else:
    print("IMPOSSIBE")

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
p,q=map(int,input().split())
if (p-q)%2==1:
  print("IMPOSSIBLE")
else:
  print(abs((p-q)//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 (a+b)%2 == 0:
  print((a+b)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

Solution code:
A, B = (int(x) for x in input().split())
K = (A + B) / 2
if A == B:
  print(0)
else:
  if isinstance(K, int):
    print(K)
  else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

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("IMPOSSILBE")

Submission status: Wrong Answer

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

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:
import math
a, b = map(int, input().split())
n = abs((b - a) / 2)
k = abs((b - a) // 2)
if n != k:
    m = "IMPOSSIBLE"
elif b > a:
    m = int(b - n)
else:
    m = int(n - a)
print(m)

Submission status: Wrong Answer

Solution code:
a,b=map(int,input().split())
c=abs(a+b)/2
if c % 1 == 0:
    print(c)
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+2)/2)
else:
  print("IMPOSSIBLE")

Submission status: Wrong Answer

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

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

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
if A >= B:
  K = B + abs(A-B)/2
else:
  K = A +  abs(A-B)/2
if float.is_integer(K) == True:
  print(K)
else:
  print('IMPOSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

Solution code:
A,B = map(int,input().split())
if A >= B:
  K = B + abs(A-B)/2
else:
  K = A +  abs(A-B)/2
print(K)

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

Submission status: Wrong Answer

Solution code:
def main():
    i = list(map(int, input().split()))

    for j in i:
        if isinstance(j, int) == False:
            return
        if j < 0 or 10**9 < j:
            return
    if i[0] == i[1]:
        return

    a = int(i[0])
    b = int(i[1])

    k = (a + b)/2

    if isinstance(k, int):
        print(k)
    else:
        print('IMPOSSIBLE')

if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
def main():
    i = list(map(int, input().split()))

    for j in i:
        if isinstance(j, int) == False:
            return
        if j < 0 or 10**9 < j:
            return
    if i[0] == i[1]:
        return

    a = i[0]
    b = i[1]

    k = (a + b)/2

    if isinstance(k, int):
        print(k)
    else:
        print('IMPOSSIBLE')

if __name__ == '__main__':
    main()

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,raw_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 "." in str(a+b/2) else "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:
A, B = map(int, input().split())
if (A + B) % 2 != 0:
    print("IMPOSSIBLE")
else:
    print((A + B) / 2)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

if abs(A-buf) == abs(B-buf) :
    print(int(buf))
else :
    print('IMPOSSIBLE')

Submission status: Wrong Answer

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

K = (A+B)% 2
if K == 0:
    print(int((A+B)/2))
else:
    print('IMPSSIBLE')

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(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(int((a+b/2)))
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

Z = (a+b)%2

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

Submission status: Wrong Answer

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

Z = (a+b)%2

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

Submission status: Wrong Answer

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

Z = (a+b)%2

if Z==0:
    print(Z)
else:
    print("IMPOSSIBLE")

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

K = (A+B)% 2
if K == 0:
    print((A+B)/2)
else:
    print('IMPSSIBLE')

Submission status: Wrong Answer

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

K = (A+B)/2
if isinstance(K,int):
    print(K)
else:
    print('IMPSSIBLE')

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())

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

Submission status: Wrong Answer

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

K = (A+B)/2
if isinstance(K,int):
  print(K)
else:
  print('IMPSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

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!=0:
    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())
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==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==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==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())
print((a+b)/2)

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

w = ( A + B )

if w % 2 == 0:
    print( w / 2 )
else:
    print('IMPOSSIBLE')

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

Submission status: Wrong Answer

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

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