There are T test cases, for each test case, you will be given n (1<=n<=400000) operations for a stack.
Two possible operations:
1. push x
for operation 1 you are asked to push x(1<=x<=100000000) in to the stack. for operation 2 you are asked to pop out the top element of the stack and print the maximum number of the stack - minimum number in the stack
the first line is T(1<=T<=5).
for each case, the first line is n(1<=n<=400000) , which is the number of operations, then follows n line contains either operation 1 or operation 2.
for each pop operation, print the (MAX - MIN) value in the remains stack, if the stack is empty, print 0;
0 is because the stack is empty after the first pop;
138 is calculated by 416 - 278 = 138