Lecture 22 Objectives

At the end of today's class you should

KNOW:

That C supports multi-dimensional arrays (arrays of arrays)
That for-loops are frequently used to process arrays
That arrays are stored in row-major order in C
That programs can be made to run more efficiently by exploiting locality
That when a two-dimensional array is passed as a parameter, the number of columns must also be passed to ensure that C can calculate the address of each array element

BE ABLE TO:

Write C code to process each element of a two-dimensional array
Define spatial locality and temporal locality
Write code that accesses elements of an array so that it exploits spatial locality and temporal locality

Sample Exam Question:

Rewrite the loop in the following code so that it access the array list using pointer notation instead of using square-bracket notation:

int list[5][10], i;
int *pList;

pList = list;

// set the 0th element of each row to i
for (i=0;  i<5; i++)
  list[i][0] = i;