Bài giảng Tin học đại cương - Chương 5: Pointers and Strings

1 Chapter 5 - Pointers and Strings Outline 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 Introduction Pointer Variable Declarations and Initialization Pointer Operators Calling Functions by Reference Using constwith Pointers Bubble Sort Using Pass-by-Reference Pointer Expressions and Pointer Arithmetic Relationship Between Pointers and Arrays Arrays of Pointers Function Pointers Introduction to Character and String Processing 5.11.1 Fundamentals of Characters and Strings 5.11.2 String Manipulation Functions of the String- Handling Library  2003 Prentice Hall, Inc. All rights reserved. Pointer Variable Declarations 2 and Initialization • Pointer variables – Contain memory addresses as values count – Normally, variable contains specific value (direct reference) 7 – Pointers contain address of variable that has specific value (indirect reference) • Indirection countPtr count 7 – Referencing value through pointer • Pointer declarations –*indicates variable is pointer int *myPtr; declares pointer to int, pointer of type int * – Multiple pointers require multiple asterisks int *myPtr1, *myPtr2;  2003 Prentice Hall, Inc. All rights reserved. Pointer Variable Declarations and 3 Initialization • Can declare pointers to any data type • Pointer initialization – Initialized to 0, NULL, or address •0or NULLpoints to nothing  2003 Prentice Hall, Inc. All rights reserved. 4 Pointer Operators •&(address operator) – Returns memory address of its operand – Example int y = 5; int *yPtr; yPtr = &y; // yPtr gets address of y –yPtr“points to” y y yptr yPtr 5 500000 600000 y 600000 5 address of y is value of yptr  2003 Prentice Hall, Inc. All rights reserved. 5 Pointer Operators •*(indirection/dereferencing operator) – Returns synonym for object its pointer operand points to –*yPtrreturns y(because yPtrpoints to y). – dereferenced pointer is lvalue *yptr = 9; // assigns 9 to y •* and &are inverses of each other  2003 Prentice Hall, Inc. All rights reserved. ... - tailieumienphi.vn