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HTML

CSS

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JavaScript

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HTML

              
                
              
            
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CSS

              
                
              
            
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JS

              
                  var inputStack = []; // First stack
  var outputStack = []; // Second stack

  // For enqueue, just push the item into the first stack
  function enqueue(stackInput, item) {
    return stackInput.push(item);
  }

  function dequeue(stackInput, stackOutput) {
    // Reverse the stack such that the first element of the output stack is the
    // last element of the input stack. After that, pop the top of the output to
    // get the first element that was ever pushed into the input stack
    if (stackOutput.length <= 0) {
      while(stackInput.length > 0) {
        var elementToOutput = stackInput.pop();
        stackOutput.push(elementToOutput);
      }
    }

    return stackOutput.pop();
  }

              
            
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999px

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