It is not a mathematical operation at all. It is a description of an economic process in speculative markets.
The price of an asset falls. This may induce some long-term investors to sell and thereby add to available supply and reduce the asset’s price even further. Nothing, however, forces long-term investors to sell so the term “squeeze” is not really appropriate though often used. The situation is different with speculators who borrowed money on a secured basis to acquire the asset. Those speculators must either increase the collateral supporting the loan or sell the asset. Those speculators who do not have sufficient additional collateral must sell. This is what makes it a “squeeze”: some speculators have no option, and their forced actions further depress the price of the asset.
What two? Are you asking about a short squeeze.