Design a reasonably efficient algorithm for solving each of the following problems and determine its efficiency class. a. You are given n telephone bills and m checks sent to pay the bills (n ≥ m).Assuming that telephone numbers are written on the checks, find out who failed to pay. (For simplicity, you may also assume that only one check is written for a particular bill and that it covers the bill in full.)

Design a reasonably efficient algorithm for solving each of the following problems and determine its efficiency class.

a. You are given n telephone bills and m checks sent to pay the bills (n ≥ m).
Assuming that telephone numbers are written on the checks, find out who failed to pay. (For simplicity, you may also assume that only one check is written for a particular bill and that it covers the bill in full.)