Sams Teach Yourself C in 21 Days

3. If conditionevaluates to false (that is, it is equal to zero), the forstatement termi-
   nates and execution passes to the first statement following statement.


4. If conditionevaluates to true (that is, it is equal to a nonzero value), the C state-
   ment(s) in statementare executed.


5. The expression incrementis evaluated, and execution returns to step 2.
   Figure 6.1 shows the operation of a forstatement. Note that statementnever executes if
   conditionis false the first time it’s evaluated.

126 Day 6

FIGURE6.1

A schematic represen-

tation of a forstate-

ment.

Evaluate

initial

Evaluate

increment

Start

Evaluate

condition

Done

Execute

statements

for (initial; condition; increment)

statements

TRUE

FALSE

Listing 6.1 presents a simple example by using a forstatement to print the numbers 1

through 20. You can see that the resulting code is much more compact than it would be if

a separate printf()statement were used for each of the 20 values.

LISTING6.1 forstate.c. A simple forstatement

1: /* Demonstrates a simple for statement */

2:

3: #include <stdio.h>

4:

5: int count;

6:

7: int main( void )

8: {

9: /* Print the numbers 1 through 20 */

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