36 lines
535 B
Plaintext
36 lines
535 B
Plaintext
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stack = {count: 0, head: none};
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fun push(stack, value)
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{
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node = {prev: none, item: value};
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node.prev = stack.head;
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stack.head = node;
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stack.count = stack.count + 1;
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}
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fun pop(stack)
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{
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if stack.head == none:
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return none; # return it; ?
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value = stack.head.item;
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stack.head = stack.head.prev;
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stack.count = stack.count - 1;
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return value;
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}
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push(stack, 1);
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push(stack, 2);
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push(stack, 3);
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x = pop(stack);
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y = pop(stack);
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z = pop(stack);
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w = pop(stack);
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assert(x == 3);
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assert(y == 2);
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assert(z == 1);
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assert(w == none); |