tables.java

Beginning Java 2, SDK 1.4 Edition Exercise Code samples for this book

//Chapter 4, Exercise 2

public class Tables {
  public static void main(String[]args) {
    final int TABLE_SIZE = 12;
    // Declare the rectangular array to store the multiplication table:
    int[][] table = new int[TABLE_SIZE][TABLE_SIZE];

    // Fill in the array with the multiplication table:
    for(int i = 0 ; i<table.length ; i++) {
      for(int j = 0 ; j<table[i].length ; j++) {
        table[i][j] = (i+1)*(j+1);
      }
    }

    // Output the table heading
    System.out.print("      :");             // Row name column heading
    for(int j = 1 ; j<=table[0].length ; j++) {
      System.out.print((j<10 ? "   ": "  ") + j);
    }
    System.out.println("\n-------------------------------------------------------");
    
    // Output the table contents
    // Each entry in the table should be four characters wide so we output
    // three spaces preceding values less than 10, two spaces preceding values
    // from 10 to 99 and one space for values exceeding 100.
    for(int i=0; i<table.length; i++) {
	  System.out.print("Row" + (i<9 ? "  ":" ") + (i+1) + ":");

      for(int j=0; j<table[i].length; j++) {
	        System.out.print((table[i][j]<10 ? "   " : table[i][j]<100 ? "  " : " ") + table[i][j]);
      }
      System.out.println();
    }
  }
}