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Our Chef is currently practicing on CodeChef and is a beginner. The count of ‘All Problems’ in the Beginner section is X. Our Chef has already ‘Attempted’ Y problems among them. How many problems are yet ‘Un-attempted’?

------ Input Format ------ 

- The first and only line of input contains two space-separated integers X and Y — the count of 'All problems' in the Beginner's section and the count of Chef's 'Attempted' problems, respectively. 

------ Output Format ------ 

Output a single integer in a single line — the number of problems that are yet 'Un-attempted'

------ Constraints ------ 

$1 ≤ Y ≤ X ≤ 1000$

------ subtasks ------ 

Subtask 1 (100 points):
Original constraints.

----- Sample Input 1 ------ 
10 4
----- Sample Output 1 ------ 
6
----- explanation 1 ------ 

----- Sample Input 2 ------ 
10 10
----- Sample Output 2 ------ 
0
----- explanation 2 ------ 

----- Sample Input 3 ------ 
1000 990
----- Sample Output 3 ------ 
10
----- explanation 3 ------ 

----- Sample Input 4 ------ 
500 1
----- Sample Output 4 ------ 
499
----- explanation 4 ------ 
Test case $1$: There are $10$ problems in total in the Beginner's section, out of which $4$ have been attempted. Hence, there are $6$ Un-attempted problems.

Test case $2$: There are $10$ problems in total in the Beginner's section, out of which all have been attempted. Hence, there are $0$ Un-attempted problems.

Test case $3$: There are $1000$ problems in total in the Beginner's section, out of which $990$ have been attempted. Hence, there are $10$ Un-attempted problems.

Test case $4$: There are $500$ problems in total in the Beginner's section, out of which only $1$ has been attempted. Hence, there are $499$ Un-attempted problems.

Source: codechef | Difficulty: EASY


Solutions:
(X, Y) = map(int, input().split())
print(X - Y)


(x, y) = map(int, input().split(' '))
print(x - y)


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


(p, q) = map(int, input().split())
print(p - q)


(x, y) = map(int, input().split())
if x > y:
	print(x - y)
else:
	print(0)


(n_prob, chef_done) = map(int, input().split())
print(n_prob - chef_done)


a = input().split(' ')
b = int(a[0])
v = int(a[-1])
print(b - v)


(attempted, unattempted) = map(int, input().split())
print(attempted - unattempted)


k = 0
(a, b) = list(map(int, input().split()))
k = a - b
print(k)


inpt = [int(x) for x in input().split()]
x = inpt[0]
y = inpt[1]
print(x - y)


(x, y) = list(map(int, input().split()))
no_of_prodone = x - y
print(no_of_prodone)


(x, y) = input().split()
x = int(x)
y = int(y)
z = x - y
print(z)


def problems():
	a = list(map(int, input().split()))
	print(a[0] - a[1])
problems()


(X, Y) = map(int, input().split())
if X > Y:
	print(X - Y)
elif X == Y:
	print(X - Y)


(a, x) = map(int, input().split())
print(a - x)


(totalProblem, totalAttemptProblem) = map(int, input().split())
print(totalProblem - totalAttemptProblem)


(t, a) = map(int, input().split())
print(t - a)


(a, b) = [int(x) for x in input().split()]
print(a - b) if a >= b else print('0')


nums = list(map(int, input().split()))
print(nums[0] - nums[-1])


(B, P) = map(int, input().split())
print(B - P)


(problems, attempted) = map(int, input().split(' '))
print(problems - attempted)


(totalProbs, attempted) = [int(x) for x in input().split()]
print(totalProbs - attempted)


l = list(map(int, input().strip().split()))
print(l[0] - l[1])


(n, m) = map(int, input().split())
print(n - m)


(s, k) = map(int, input().split())
print(s - k)