Python Notes---day2:while loops

1. String Integration:

+ No spacing of output results

, spacing of output results

2. Arithmetic operators:

divisible

% Take remainder

* * prescribe

! = does not equal

3. Assignment operators:

A+=1 equivalent to a+1, a*=2 equivalent to a*2

4. Logical operators:

and tie relationships

or or

not non-

Priority:Not>and>or

Short-circuit principle: in two conditions to determine the condition 1, sometimes no longer need to look at other conditions

5. output 1 to All even numbers:

A=1

While a<50:

If a%2==1:

A+=1

Else

Print (a)

A+=1

Print ("End")

6, give the reminder cycle guess Age:

Age=50

Flag=true Adding a state variable

While flag:

Guess=int (Input ("Guess Age:"))

If Guess==age:

Print ("right!")

Flag=false Correct seasonal state variable to jump out while loop

Elif Guess>age:

Print ("Too big")

Else

Print ("Too small")

Print ("End")

7. Other directives:

Break Terminate Loop

Continue jump out of the loop

End= "_" takes _ as the end of the sentence and does not break the line

Print () represents print (end= "\ n"), which is a newline

The else statement after the while is run when the while is at a normal end, that is, When there is no break

8, According to user demand output line and width:

H=int (Input ("Height:"))

W=int (Input ("width:"))

Nh=1

While Nh<=h:

Nw=1 width must be changed once per line, so it is placed within the while loop

While Nw<=w:

Print ("#", end= "")

Nw+=1 across the line.

Print () line break

Nh+=1

Note: Nesting loops, writing simple loops, and substituting ideas into another loop

9, 99 multiplication table:

Hang=1

While hang<=9:

Lie=1

While Lie<=hang:

Print (str (LIE) + "*" +str (hang) + "=" +str (Lie*hang), end= "\ T")

Lie+=1

Print ()

Hang+=1

Note: the connection of strings;"\ t" means tab; Use tab instead of space to make the table neat

Python notes---day2:while loops