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What is a LOOP?
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the loop
Until I can hear the song Make it louder
Loops repeat as long as something is true
If statements are just simple decision-making statements.
A condition is checked and something may or may not happen based on the evaluation of that condition.
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the loop
As long as I am hungry I eat something
While I have pretzels I eat one
If statements are just simple decision-making statements.
A condition is checked and something may or may not happen based on the evaluation of that condition.
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Loop Demonstration
loop if ( student is hungry and more pretzels left ) { student will eat pretzel stick }
condition
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Loops are used to repeat a command or set of commands forever or for a set number of times.
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When the green flag is clicked, the Bug will say "looping" for 2 seconds and then wait 2 seconds before saying it again. This loop will run forever.
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open
loop_one.sb
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When the green flag is clicked, the Bug will say "looping" for 2 seconds and then wait 2 seconds before saying it again. This loop will run 5 times and then stop.
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open
loop_two.sb
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What is
an If?
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the if statement
if I am hungry I eat something
if I am tired I go to sleep
If statements are just simple decision-making statements.
A condition is checked and something may or may not happen based on the evaluation of that condition.
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the if statement
if it is dark I turn a light on
if I can’t hear the song I make it louder
If statements are just simple decision-making statements.
A condition is checked and something may or may not happen based on the evaluation of that condition.
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When the green flag is clicked, the Bug will say ouch each time it is clicked with the mouse.
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open
if_one.sb
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When the green flag is clicked, the Bug move back and forth across the screen. He will say Wow and Yahoo if he is at a certain position on the screen.
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open
if_two.sb
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Complete a
Scratch Lab.
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