The For Statement

The 'for' loop is more compact than the 'while' and 'do' loops and automatically updates the loop counter at the end of each iteration. Both 'for' and 'while' loops are designed for different situations. You'll learn more about when to use each later.

7. Small Change



Small Change

The change part can be complicated, if you want. It is best to keep it small and understandable. Here is almost the same loop as in the previous example, but now the control variable is incremented by two.

The expression count += 2 adds the value 2 to the variable count. (For more details on this see chapter 31.) Try to predict the output before you run the program.

The change to count is done at the bottom of the loop body. This means that the last value that count gets is the first one that fails the test count < 7. This is the value count will have just outside the loop body.

Questions like this are common on midterm and final examinations. If you rush, you are likely to get them wrong. But with careful thought they are easy enough.

int count;
for ( count = 0; count < 7; count += 2 )
System.out.println( "count is: " + count );
System.out.println( "\nDone with the loop.\nCount is now" + count);


Question 7:

Read the description, and then fill in the blanks of the sequence. Then fill in the blanks of the loop that creates the same sequence.

    descriptionstart at 1, count upward by 2's, all values less than 10
    codefor ( count =  ; count   )