number = int(input())
 
my_stack = []
 
for _ in range(number):
    query = input()
    
    query_split = query.split()
    command = query_split[0]
    
    if command == "1":
        current_number = int(query_split[1])
        my_stack.append(current_number)
        
    elif command == "2" and my_stack:
        my_stack.pop()
    
    elif command == "3" and my_stack:
        print(max(my_stack))
    
    elif command == "4" and my_stack:
        print(min(my_stack))
    
        
reversed_stack = []        
while my_stack:
    reversed_stack.append(str(my_stack.pop()))
    
print(", ".join(reversed_stack))