Ambidentate ligands are ligands that can bond to a metal atom through two different atoms. They can attach through one site or the other, but not both at the same time.

In the given complex $$[\mathrm{M}(\mathrm{en})(\mathrm{SCN})_{4}]$$:

• $$\mathrm{en}$$, or ethylenediamine, is a bidentate ligand, meaning it can form two bonds with the metal ion, but it is not ambidentate because it always binds through the same two nitrogen atoms.

• $$\mathrm{SCN}^{-}$$, on the other hand, is an example of an ambidentate ligand. It can bind to the metal either through the sulfur atom ($$\mathrm{S}$$) or the nitrogen atom ($$\mathrm{N}$$).

Since there are four $$\mathrm{SCN}^{-}$$ ligands in the given complex, the number of ambidentate ligands is 4.