Step 1: Structure of \(XeO_3\).
In \(XeO_3\), xenon forms three \(Xe=O\) double bonds.
Each double bond contains one \(\pi\)-bond.
So total \(\pi\)-bonds:
\[
3
\]
Step 2: Structure of \(XeO_4\).
In \(XeO_4\), xenon forms four \(Xe=O\) bonds in tetrahedral structure.
Each has one \(\pi\)-bond.
So total \(\pi\)-bonds:
\[
4
\]
Final Answer:
\[
\boxed{3,4}
\]