C++ How to Program, 10/e

D.1 Introduction

In this appendix, we introduce the key number systems that C++ programmers use, especially when they are working on software projects that require close interaction with machine-level hardware. Projects like this include operating systems, computer networking software, compilers, database systems and applications requiring high performance.

When we write an integer such as 227 or –63 in a C++ program, the number is assumed to be in the decimal (base 10) number system. The digits in the decimal number system are 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. The lowest digit is 0 and the highest is 9—one less than the base of 10. Internally, computers use the binary (base 2) number system. The binary number system has only two digits, namely ...