P2944 [USACO09MAR] Earthquake Damage 2 G

Wisconsin has had an earthquake that has struck Farmer John's farm! The earthquake has damaged some of the pastures so that they are unpassable. Remarkably, none of the cowpaths was damaged. As usual, the farm is modeled as a set of P (1

\* Line 1: Three space-separated integers: P, C, and N \* Lines 2..C+1: Line i+1 describes cowpath i with two integers: a\_i and b\_i \* Lines C+2..C+N+1: Line C+1+j contains a single integer: report\_j

\* Line 1: One number, the minimum number of damaged pastures.

Only pasture 2 being damaged gives such a scenario.