class QueueUsingTwoStacks:
    def __init__(self):
        self.primary_stack = []
        self.temp_stack = []
        
    def enqueue(self, item):
        self.primary_stack.append(item)
        
    def dequeue(self):
        if self.is_empty():
            return None
        
        if not self.temp_stack:
            while self.primary_stack:
                self.temp_stack.append(self.primary_stack.pop())
            
        return self.temp_stack.pop()
        
    def peek(self):
        if self.is_empty():
            return None
        
        if not self.temp_stack:
            while self.primary_stack:
                self.temp_stack.append(self.primary_stack.pop())
            
        return self.temp_stack[-1]
        
    def is_empty(self):
        return len(self.primary_stack) == 0 and len(self.temp_stack) == 0
        
if __name__ == '__main__':
    queue = QueueUsingTwoStacks()
    Q = int(input())
    queries = []
    for _ in range(Q):
        queries.append(list(map(int, input().split())))

    for query in queries:
        cmd = query[0]
        if cmd == 1:
            item = query[1]
            queue.enqueue(item)
        elif cmd == 2:
            queue.dequeue()
        else:
            print(queue.peek())