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petri foxx
336 Pointsvery difficult to understand.. need more examples
I could not understand this lesson.. I wish and hope that you explain it in different way, and more examples . thx U in advance.
6 Answers
Bernard Paulet
3,364 PointsThe basic difference between While loop and Do..While loop is that : -While loop tests the condition before going through the loop block instructions
- Do..While loop performs first the loop block of instructions and then tests the condition
Green Coding
1,416 Pointsthe while loop will only work if the condition is true
var i = 0
while i=1 {
println("I looped")
i++
} \\it won't execute
However, the do while loop will do it once and then check if the condition is true
var i = 0
do {
println("I looped")
}while i=1
\\the statement will run once
So...the difference is that the do while loop will execute even when the condition isnt true but the while loop only executes if the condition is true
Bobby T
1,010 PointsIt should be noted that:
while i = 1
needs to be changed to:
while i == 1
because while is always checking for a boolean True or False, and the = sign is an assignment operator while == is a comparison operator
petri foxx
336 Pointsthe example are not working in Playground and while they do not working or print out nothing .. so I do not understand them why they are the way they are!!!!
petri foxx
336 Pointswhat I can understand the difference between while and do, that while will not work in advance , but "do" will go through the code even if not work.. but what is the meaning if "do" will go through the code while it does NOT work !!!! no logic !
Green Coding
1,416 PointsPetri, I don't think you understand. There is logic and a use for the do-while, for instance, lets say you wanted to make a game where you spun a wheel. It cost money to spin the wheel. However, every day you wanted to give someone a free spin.
var ifIHaveSpunToday = false
do {
spinWheel \you haven't covered functions yet so just pretend like you can say spin wheel and it will spin
ifIHaveSpunToday = True
} while == false
This way, the person will get to spin once if they havent spun yet, then the computer will know they have spun, and then the computer will check the condition to make sure it works-- but it won't, you have already spun.
And yes you could do this with a while loop...but this is just one example of a do while being better programming when needed
petri foxx
336 Pointsthis code above did not work in my side !! in your answer your wrote:
do while loop will execute even when the condition isn't true
but your code below does not work in my Playground compiler
do { println("I looped") }while i=1 \the statement will run once
Green Coding
1,416 PointsSorry! I accidentally had my comparitave operator syntax wrong. I edited my previous post and now it will work. I did this on playground to helo you '''swift
var i = 5
while i == 0 {
println("I Looped")
i++
}
do {
println("I looped from the do")
} while i == 0 '''