43 lines
1.1 KiB
Java
43 lines
1.1 KiB
Java
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Using HashMap to store number of words
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import java.util.*;
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public class HashMapTest
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{
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private static String names[] = { "one", "two", "three",
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"four", "five", "six",
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"seven", "two", "ten", "four" };
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public HashMapTest()
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{
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HashMap m = new HashMap();
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Integer i;
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for ( int k = 0; k < names.length; k++ )
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{
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i = ( Integer ) m.get( new Character( names[ k ].charAt( 0 ) ) );
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// if key is not in map then give it value one
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// otherwise increment its value by 1
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if ( i == null )
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m.put( new Character( names[ k ].charAt( 0 ) ), new Integer( 1 ) );
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else
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m.put( new Character( names[ k ].charAt( 0 ) ), new Integer( i.intValue() + 1 ) );
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}
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System.out.println( "\nnumber of words beginning with " + "each letter: " );
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printMap( m );
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}
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public void printMap( Map mapRef )
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{
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System.out.println( mapRef.toString() );
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System.out.println( "size: " + mapRef.size() );
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System.out.println( "isEmpty: " + mapRef.isEmpty() );
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}
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public static void main( String args[] )
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{
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new HashMapTest();
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}
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}
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