importselect# 创建一个select对象selector=select.select([sys.stdin],[],[])# 循环等待输入whileTrue:# 等待输入ready_to_read,_,_=selector.select()# 如果有数据可读ifready_to_read:# 读取输入command=raw_input().lower()# 处理输入ifcommand=="commands":print'"look around"'print'...
解决While loop问题 - Python 当我们在使用while循环时,需要确保循环的终止条件最终会被满足,否则循环将会无限执行下去。通常情况下,我们可以在循环内部修改循环控制变量,使得终止条件得以满足。 1、问题背景 一位开发者在使用 Python 开发一个基于文本的游戏时,遇到了 while 循环的问题。他将游戏代码和音频处理代码结...
In the above example the loop is terminated when x becomes 5. Here we use break statement to terminate the while loop without completing it, therefore program control goes to outside the while - else structure and execute the next print statement. Flowchart: Previous:Python For Loop Next:Pytho...
The Python while loop can be used to execute a block of code for as long as a certain condition is fulfilled. While loops are primarily used in Python when the number of iterations can’t be determined at the time of writing the code. Keep reading to find out how the Python while ...
如果你對for迴圈或if陳述句不熟悉,可以閱讀〈Python for 迴圈(loop)的基本認識與7種操作〉、〈Python if 陳述句的基礎與3種操作〉。 Python while 迴圈句基本認識 先來看一個簡單的while迴圈。 例子是這樣的,你要用Python印出1到100。你可以設定一個變數i,並在while後頭陳述符合需求的條件,條件是只要i小於...
Here, we’re telling Python to break, or stop, the loop when counter is 2. Question:Why does it print each thing three times though? Answer:Look at where we do the test. We test counter after we do all of our print statements. If you put the condition in the head of the loop, ...
In Python, we use awhileloop to repeat a block of code until a certain condition is met. For example, number =1whilenumber <=3:print(number) number = number +1 Output 1 2 3 In the above example, we have used awhileloop to print the numbers from1to3. The loop runs as long as...
Python comes with two inbuilt keywords to interrupt loop iteration, break and continue. Break Keyword In While loop The break keyword immediately terminates the while loop. Let's add a break statement to our existing code, x = 1 while(x<=3): print(x) x = x + 1 if x == 3: break...
The For Loop In Python The for loop in python is used to iterate over a given sequence. The sequence can be a string, a list, a tuple,a set, a dictionary, etc. As long as the length of the sequence is not reached, it will iterate over that sequence. The for loop contains initial...
These FAQs are related to the most important concepts you’ve covered in this tutorial. Click theShow/Hidetoggle beside each question to reveal the answer. Take the Quiz:Test your knowledge with our interactive “Python while Loops: Repeating Tasks Conditionally” quiz. You’ll receive a score ...