如何设置HighCharts x轴值

I want to use HighCharts to show plot graph,
and x-axis value can be corresponded to the data value of x
but I don't know how to do this
ex:
I have data

[[201111, 10], [201112, 20], [201301, 50]] 

and make the x-axis value just the data value of x
so the x-axis value can be 201111, 201112, 201301
the plot graph has 3 plots

(201111, 10), (201112, 20), (201301, 50)

You can use tickPositions and return there array of xAxis.

Example: http://jsfiddle.net/yuw42h6e/