Oxidation state of sulfur in H2S2O5

How can I find the oxidation state of sulfur in $\ce{H2S2O5}$ using its structure?


This is the structure of $\ce{H2S2O5}$:


[![structure of H2S2O5](https://i.stack.imgur.com/5XqJ2.png)](https://i.stack.imgur.com/5XqJ2.png)




Use the states of oxygen and hydrogen to know the oxidation state of sulphur.
[![enter image description here](https://i.stack.imgur.com/LRUyp.png)](https://i.stack.imgur.com/LRUyp.png)


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