Numbers - Java - page 186

Discussion
To process a contiguous set of integers, Java provides a for loop. [ 24 ] Loop control for the
for loop is in three parts: initialize, test, and change. If the test part is initially false, the loop
will never be executed, not even once.

For discontinuous ranges of numbers, use a java.util.BitSet .

The following program demonstrates all of these techniques:

public public class class NumSeries NumSeries {

public public static static void void main ( String [] args ) {

// When you want an ordinal list of numbers, use a for loop
// starting at 1.
for for ( int int i = 1 ; i <= months . length ; i ++)

System . out . println ( "Month # " + i );

// When you want a set of array indices, use a for loop
// starting at 0.
for

for ( int int i = 0 ; i < months . length ; i ++)

System . out . println ( "Month " + months [ i ]);

// For e.g., counting by 3 from 11 to 27, use a for loop
for for ( int int i = 11 ; i <= 27 ; i += 3 ) {

System . out . println ( "i = " + i );

}

// A discontiguous set of integers, using a BitSet

// Create a BitSet and turn on a couple of bits.
BitSet b = new new BitSet ();

b . set ( 0 ); // January

b . set ( 3 ); // April

b . set ( 8 ); // September

// Presumably this would be somewhere else in the code.
for

for ( int int i = 0 ; i < months . length ; i ++) {

iif ( b . get ( i ))
System . out . println ( "Month " + months [ i ]);

}

// Same example but shorter:
// a discontiguous set of integers, using an array