Chef has a bucket having a capacity of K liters. It is already filled with X liters of water. 

Find the maximum amount of extra water in liters that Chef can fill in the bucket without overflowing.  

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

- The first line will contain T - the number of test cases. Then the test cases follow.
- The first and only line of each test case contains two space separated integers K and X - as mentioned in the problem.

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

For each test case, output in a single line, the amount of extra water in liters that Chef can fill in the bucket without overflowing.  

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

$1 ≤ T ≤ 100$
$1 ≤ X < K ≤ 1000$

----- Sample Input 1 ------ 
2
5 4
15 6

----- Sample Output 1 ------ 
1
9

----- explanation 1 ------ 
Test Case $1$: The capacity of the bucket is $5$ liters but it is already filled with $4$ liters of water. Adding $1$ more liter of water to the bucket fills it to $(4+1) = 5$ liters. If we try to fill more water, it will overflow.

Test Case $2$: The capacity of the bucket is $15$ liters but it is already filled with $6$ liters of water. Adding $9$ more liters of water to the bucket fills it to $(6+9) = 15$ liters. If we try to fill more water, it will overflow.

Source: codechef | Difficulty: EASY
Tags: Mathematics


Solutions:
t = int(input())
for i in range(t):
	(n, m) = map(int, input().split())
	print(n - m)


t = int(input())
for i in range(0, t):
	(k, y) = map(int, input().split())
	print(k - y)


t = int(input())
for i in range(t):
	(x, y) = map(int, input().split())
	print(x - y)


for _ in range(int(input())):
	(a, b) = map(int, input().split())
	print(abs(a - b))


for _ in range(int(input())):
	(k, x) = map(int, input().split())
	print(k - x)


for i in range(int(input())):
	(a, b) = map(int, input().split())
	print(a - b)


for i in range(int(input())):
	(x, y) = map(int, input().split())
	print(abs(x - y))


t = int(input())
for i in range(t):
	(x, k) = [int(x) for x in input().split()]
	print(x - k)


n = int(input())
for i in range(n):
	(p, q) = map(int, input().split())
	print(p - q)


a = int(input())
for i in range(a):
	(x, y) = map(int, input().split())
	print(x - y)


T = int(input())
for i in range(T):
	(x, y) = input().split()
	A = int(x)
	B = int(y)
	print(A - B)


t = int(input())
for _ in range(t):
	(a, b) = map(int, input().split())
	print(a - b)


t = int(input())
for i in range(t):
	(k, x) = map(int, input().split())
	extra_water = k - x
	print(extra_water)


n = int(input())
for i in range(0, n):
	(a, b) = map(int, input().split())
	print(a - b)


T = int(input())
for t in range(T):
	(K, X) = map(int, input().split())
	print(K - X)


T = int(input())
for i in range(T):
	(K, X) = map(int, input().split())
	print(K - X)


n = int(input())
for k in range(n):
	m = input().split()
	print(int(m[0]) - int(m[1]))


n = int(input())
for i in range(n):
	(x, y) = map(int, input().split())
	print(x - y)


n = int(input())
while n != 0:
	(a, b) = map(int, input().split())
	print(abs(a - b))
	n -= 1


n = int(input())
for i in range(0, n):
	(k, x) = map(int, input().split(' '))
	print(k - x)


t = int(input())
for i in range(t):
	(K, X) = map(int, input().split())
	print(K - X)


t = int(input())
for i in range(t):
	(a, b) = map(int, input().split())
	print(abs(a - b))


T = int(input())
for i in range(T):
	(x, y) = list(map(int, input().split()))
	print(x - y)


t = int(input())
while t != 0:
	(a, b) = map(int, input().split())
	print(a - b)
	t = t - 1


t = int(input())
for i in range(t):
	l = list(map(int, input().split()))
	print(l[0] - l[1])


t = int(input())
while t:
	(k, x) = map(int, input().split())
	print(k - x)
	t -= 1


for _ in range(int(input())):
	(j, x) = map(int, input().split())
	print(j - x)


t = int(input())
for i in range(t):
	(K, X) = map(int, input().split())
	if K == X:
		print(0)
	elif K > X:
		print(K - X)
	elif X > K:
		print(0)


T = int(input())
for i in range(0, T):
	(K, X) = map(float, input().split())
	a = int(K - X)
	print(a)


for i in range(int(input())):
	(k, x) = map(int, input().split())
	print(k - x)


n = int(input())
for i in range(n):
	(n1, n2) = map(int, input().split())
	print(n1 - n2)


T = int(input())
for _ in range(T):
	(x, y) = map(int, input().split())
	print(x - y)


t = int(input())
for i in range(t):
	(X, Y) = map(int, input().split())
	T = X - Y
	print(T)


t = int(input())
for i in range(t):
	(x, k) = map(int, input().split())
	if x > k:
		print(x - k)
	else:
		print('0')


x = int(input())
for i in range(x):
	a = [int(z) for z in input().split()]
	print(a[0] - a[1])


T = int(input())
while T > 0:
	l = list(map(int, input().split()))
	K = l[0]
	X = l[1]
	print(K - X)
	T = T - 1


for i in range(int(input())):
	(s, k) = map(int, input().split())
	print(abs(s - k))


x = int(input())
for i in range(x):
	(a, b) = list(map(int, input().split()))
	print(a - b)


T = int(input())
for tc in range(T):
	(n, x) = map(int, input().split())
	print(n - x)