Write a program to implement multiple timers using a single clock. Input for this program consists of a sequence of four types of commands $(S<int> , T<int>, E<int> , P<int>): S<int> $ sets the current time to $<int>; T$ is a clock tick; and $E<int>$ schedules a signal to occur at time $<int>; P$ prints out the values of Current time, Next signal, and Clock header. Your program should also print out a statement whenever it is time to raise a signal.