Question

Write a program using a for loop, while loop, and a do while loop all within the same program. The program will output the following numbers 3 times, one for each type of loop, including the string preceding each loop as below.

Answer 1

The “for” loop produces!
5
4
3
2
1

Answer 2

The “while” can do the same thing!
5
4
3
2
1

Answer 3

Don’t forget about the “do while” loop. It can do the same thing!
5
4
3
2
1

Answer 4

programming language is java

Answer 5

So let’s start off with what all of these loops start with.

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public class Main { public static void main(String[] args) { } }
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Answer 6

Now let’s look at our `for` loop, `while` loop, and `do while` loops.

FOR loop:
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public class Main { public static void main(String[] args) { for (int i = ?; i > ?; i??) { System.out.println(i); } } }
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Look at that closely and let’s piece this out,
(int i = ?;- this describes what the value of i is, which for 54321 needs to be valued at 5
i > ?; - this shows what the loop should do, “i is greater than ?”, so this means that ? should be 0 so the loop counts down
i??) - this can have 2 values, positive (++) and negative (--), and to go from 5 to 0, you subtract, so we need --

So you get this
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public class Main { public static void main(String[] args) { for (int i = 5; i > 0; i--) { System.out.println(i); } } }
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And would print out:
`5`
`4`
`3`
`2`
`1`

Answer 7

WHILE loop:
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public class Main { public static void main(String[] args) { int i = ?; while (i > ?) { System.out.println(i); i??; } } }
————————

This one will simply run through the printout code and then go down a number, using the same portions (below)

int i = ?;- this describes what the value of i is, which for 54321 needs to be valued at 5 like FOR loop was
i > ?; - this shows what the loop should do, “i is greater than ?”, so this means that ? should be 0 so the loop counts down
i??) - this can have 2 values, positive (++) and negative (--), and to go from 5 to 0, you subtract, so we need --

So you get this
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public class Main { public static void main(String[] args) { int i = 5; while (i > 0) { System.out.println(i); i--; } } }
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And would print out:
`5`
`4`
`3`
`2`
`1`

Answer 8

WHILE loop:
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public class Main { public static void main(String[] args) { int i = ?; do { System.out.println(i); i??; } while (i > ?); } }
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Same as the others, except it goes,
“Do [action: printout 5/subtract 1] - while [value: i is greater than 0]
So you get this
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public class Main { public static void main(String[] args) { int i = 5; do { System.out.println(i); i--; } while (i > 0); } }
————————
And would print out:
`5`
`4`
`3`
`2`
`1`