Class 17: Array Basics

Held: Monday, 17 February 2003

Summary: Today we consider the representation of arrays in C.

Related Pages:

• EBoard.
• Lab on Arrays.

Assignments:

• Read Gries, Chapter 5.

Overview:

• Representing arrays.
• Representing multi-dimensional arrays.
• Key array operations.
• Lab.

Representing Arrays

• Sequence of contiguous memory.
• a[i] is at "start of a + i*sizeof(each element)"
• Alternatives?
• Advantages/disadvantages?

Representing Multidimensional Arrays

• Still a sequence of contiguous memory:
• If a is declared as a[I][J], a[i][j] is at "start of a + (i*J + j)*sizeof(each element)"
• Alternatives?
• Advantages/disadvantages?

array-operations

• Assignment: Guess.
• Use in an operation: Guess.
• Initialization: Enclose contents in braces.

  int ant[5] = { 5, 2, 7, 3, 4};
  

Lab

• Do the lab.
• Be prepared to reflect.