請問在QBasic能否用Do while loop

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Loops
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"Loops" make it easier to do an action multiple times. There are at least four types of loops: IF...GOTO , WHILE...WEND , DO...LOOP , and FOR...NEXT .


IF...GOTO

This program uses IF...GOTO to create a loop:

x = 10

start:
PRINT x

x = x + 1 (This adds 1 to x)

IF x < 15 THEN GOTO start
Output:10
11
12
13
14

WHILE...WEND

The WHILE...WEND commands continue a loop until a specified expression is false.

To use WHILE...WEND :Place an expression after WHILE
Enter a list of commands
Place WEND at the end


Run the following:x = 10

WHILE x < 15

PRINT x

x = x + 1

WEND Output (same as in previous example):10
11
12
13
14

DO...LOOP

DO...LOOP is exactly the same as WHILE...WEND , except it has at least two slight advantages. With DO...LOOP you can:Loop until an expression is true
Loop at least one time regardless of whether the expression is true or not.


To use DO...LOOP :Specify whether the loop continues "while" the expression is true or "until" the expression is true, using the WHILE and UNTIL statements, respectively.
Place an expression after WHILE / UNTIL
Enter a list of commands
Place LOOP at the end


The following uses the WHILE statement:x = 10

DO WHILE x < 15

PRINT x

x = x + 1

LOOP
This program uses the UNTIL statement:x = 10

DO UNTIL x = 15

PRINT x

x = x + 1

LOOP
They both output:10
11
12
13
14

If you place the expression at the end of the loop instead, the program goes through the loop at least once.x = 32

DO

PRINT x

x = x + 1

LOOP WHILE x < 5 This is the output because the loop was only gone through one time:32