1주차 - 스택 & 큐

1. 스택(Stack; 쌓다)

• push : 입력
• peek : 가장 마지막으로 입력된 값 확인
• pop  : 가장 마지막으로 입력된 값 꺼내오기

 

• Stack 함수 직접 구현하기

  • # Stack 함수 직접 구현하기
    class Stack(list):
    	push = list.append
        
        def peek(self):
        	return self[-1]
            
    s = Stack
    s.push(1)
    s.push(2)
    s.push(3)
    
    print("my stack is: ", s)
    # my stack is: [1, 2, 3]
    
    print("popped value is: ", s.pop())
    # popped value is: 3
    
    print("my stack is: ", s)
    # my stack is: [1, 2] 
    
    print("peeked value is: ", s.peek())
    # peeked value is: 2
    
    print("my stack is: ", s)
    # my stack is: [1, 2]

• List를 스택으로.

  • # list를 스택으로 활용
    
    s = []
    
    s.append(1)
    s.append(2)
    s.append(3)
    
    print("my stack is: ", s)
    # my stack is: [1, 2, 3]
    
    print("popped value is: ", s.pop())
    # popped value is: 3
    
    print("my stack is: ", s)
    # my stack is: [1, 2]
    
    print("peeked value is: ", s[-1])
    # peeked value is: 2
    
    print("my stack is: ", s)
    # my stack is: [1, 2]

 

2. 큐(Queue; 일이 처리되기를 기다리는 리스트)

• put   : 입력
• peek : 가장 먼저 입력된 값 확인
• get   : 가장 먼저 입력된 값 꺼내오기

 

• Queue 함수 직접 구현하기

  • class Queue(list):
    	put = list.append
        
        def peek(self):
        	return self[0]
            
        def get(self):
        	return self.pop(0)
            
    q = Queue()
    q.put(1)
    q.put(2)
    q.put(3)
    
    print("my queue is: ", q)
    # my queue is: [1, 2, 3]
    
    print("removed value is: ", q.get())
    # removed value is: 1
    
    print("my queue is: ", q)
    # my queue is: [2, 3]
    
    print("peeked value is: ", q.peek())
    # peeked value is: 2
    
    print("my queue is: ", q)
    # my queue is: [2, 3]

• Queue 클래스 import 

  • from queue import Queue
    
    q = Queue()
    q.put(1)
    q.put(2)
    q.put(3)
    
    print("my queue is: ", q)
    # my queue is: [1, 2, 3]
    
    print("removed value is: ", q.get())
    # removed value is: 1
    
    print("my queue is: ", q)
    # my queue is: [2, 3]
    
    print("peeked value is: ", q.peek())
    # peeked value is: 2
    
    print("my queue is: ", q)
    # my queue is: [2, 3]

• List를 큐로 

  • # list를 큐로 활용
    
    q = []
    
    q.append(1)
    q.append(2)
    q.append(3)
    
    print("my queue is: ", q)
    # my queue is: [1, 2, 3]
    
    print("removed value is: ", q.pop(0))
    # removed value is: 1
    
    print("my queue is: ", q)
    # my queue is: [2, 3]
    
    print("peeked value is: ", q[0])
    # peeked value is: 2
    
    print("my queue is: ", q)
    # my queue is: [2, 3]