THE BASICS OF COUNTING Suppose that a password on a computer system consists of six, seven, or eight characters. completely(prenominal) of these characters essential be a digit or a letter of the alphabet. Each password must contain at least(prenominal) one digit. How numerous such passwords ar thither? The techniques make to answer this question and a wide variety of former(a) cast up uping problems forget be introduced in this section. Counting problems repeal throughout mathematics and computer science. For example, we must count the booming outcomes of experiments and all the possible outcomes of these experiments to determine probabilities of discrete events. We need to count the make sense of operations used by an algorithm to have its clock complexity. We will introduce the basic techniques of numerate in this section. These methods divine service as the foundation for almost all counting techniques. We will present two basic counting principles, the produce chemical formula and the sum rule. THE PRODUCT RULE Suppose that a agency can be broken down into a eon of two tasks. If thither are n_1 ways to do the counterbalance task and for each of these ways of doing the first task, there are n_2 ways to do the second task, then there are n_1n_2 ways to do the procedure. Example 1. A wise telephoner with just two employees, Sanchez and Patel, rents a floor of a construction with 12 offices. How many ways are there to introduce contrary offices to these two employees? Example 2. The chairs of an auditorium are to be approximate with a letter and a positive integer not exceeding 100. What is the largest number of chairs that can be labeled otherwise? Example 3. There are 32 microcomputers in a computer center. Each microcomputer has 24 ports. How many different ports to a microcomputer in the center are there? An extended version of the product rule is a bunch useful. Suppose that a procedure is carried ou t by do the tasks T_1 , T_2 , . . . , T_m i! n sequence. If each task T_i , i = 1, 2, . . . , m, can be done in n_i ways,...If you want to get a healthy essay, order it on our website: OrderCustomPaper.com
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