The following notes summarize the main ideas of Chapter 0. Some supplementary material has been provided.
Algorithm:
An ordered set of unambiguous executable steps that define a terminating activity.
Note: The word algorithm may be traced back to the 9th century when an Arabic mathematician Al-Kowarizmi wrote a book called Al-Jebr.
Important events in the development of Computing:
Abstraction:
The following notes summarize the main ideas of Chapter 1. Some supplementary material has been provided.
Binary Digits:
Electronic hardware devices have two natural states. Designers of electronic computers use this fact to greatly simplify the design of electronic computers. However, because long sequences of 0's and 1's are difficult to read and understand, binary digits are conventionally grouped to make them more comprehensible. The term bit is used to refer to a single binary digit. The following list shows the terms often used to denote groups of binary digits.
Binary Notation:
See page 38 of the text. Particularly figures 1.13 and 1.14.
Converting Binary to Decimal
Make use of positional notation to complete the conversion. That is,
if you consider the rightmost binary digit to be position zero, then
as you move from right to left, each binary digit, corresponds to
2n
where n is the position of the digit.
e.g. The binary number 1001101
=
1*26 +
0*25 +
0*24 +
1*23 +
1*22 +
0*21 +
1*20
= 64 + 8 + 4 + 1 = 77.
Converting Decimal to Binary
The following algorithm is similar to that presented in the text. Either version is acceptable.
Write down the remainders obtained at step 2 in reverse order to get the binary equivalent of the decimal number.
Practice Problems
Work problems 5-6 on page 44 and 1-2 on page 47 of the text. Answers are in the back of the book.