22 lines
654 B
Markdown
22 lines
654 B
Markdown
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# STACK
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stack is an ADT (abstract data type ) that act like list of objects but there is a diffrents.
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stack act is *LIFO* (Last In First Out), it means that when we want to get an element from the stack we get the last element in the stack.
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stack is bast on two methods ( functions)
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## push & pop
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**push**: add an alement to last index of stack.
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for example: we have `1, 3, 5` in stack, then we call push(9),
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`9` will add to last index of stack -> `1, 3, 5 , 9`
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**pop**: remove the last element from stack.
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for example: we have `1, 3, 5 , 9` in stack, then we call pop(),
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the function will return `9` and the stack will change to `1, 3, 5`.
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