B'Alex is solving a problem. He has n constraints on what the integer k can be. There are three types of constraints: Help Alex find the number of integers k that satisfy all n constraints. It is guaranteed that the answer is finite (there exists at least one constraint of type 1 and at least one constraint of type 2 ). Also, it is guaranteed that no two constraints are the exact same. Each test consists of multiple test cases. The first line contains a single integer t ( 1 <= q t <= q 500 ) -- the number of test cases. The description of the test cases follows. The first line of each test case contains a single integer n ( 2 <= q n <= q 100 ) -- the number of constraints. The following n lines describe the constraints. Each line contains two integers a and x ( a in {1,2,3 }, , 1 <= q x <= q 10^9 ). a denotes the type of constraint. If a=1 , k must be greater than or equal to x . If a=2 , k must be less than or equal to x . If a=3 , k must be not equal to x . It is guaranteed that there is a finite amount of integers satisfying all n constraints (there exists at least one constraint of type 1 and at least one constraint of type 2 ). It is also guaranteed that no two constraints are the exact same (in other words, all pairs (a, x) are distinct). For each test case, output a single integer -- the number of integers k that satisfy all n constraints. In the first test case, k geq 3 and k <= q 10 . Furthermore, k neq 1 and k neq 5 . The possible integers k that satisfy the constraints are 3,4,6,7,8,9,10 . So the answer is 7 . In the second test case, k ge 5 and k <= 4 , which is impossible. So the answer is 0 . '...