发布时间 : 星期六 文章面向对象编程基础习题及答案更新完毕开始阅读
}
public static void increase(int[] x) { for (int i = 0; i < x.length; i++) x[i]++; }
public static void increase(int y) { y++; } }
Results: 2 1
9. Given the following program, show the values of the array in the following figure:
public class Test {
public static void main(String[] args) { int[] values = new int[5];
for (int i = 1; i < 5; i++) { values[i] = i;
}
values[0] = values[1] + values[4]; } } After the array is created 0 1 2 3 4 After the first iteration in the loop is done 0 1 2 3 4 After the loop is completed 0 1 2 3 4 After the last statement in the main method is executed 0 1 2 3 4
Results:
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After the array is created 0 1 2 3 4 0 0 0 0 0 After the first iteration in the loop is done 0 1 2 3 4 0 1 0 0 0 After the loop is completed 0 1 2 3 4 0 1 2 3 4 After the last statement in the main method is executed 0 1 2 3 4 5 1 2 3 4
PartV. Programming
1. (10pts) (Don?t use the if statement) Write a complete program named TrueOrFalse.java.
The program reads a double number from an input dialog box and checks whether the number is between 1 and 1000. For example, if your input is 5, the output should be: Is the number 5 between 1 and 1000? true
If your input is 2000, the output should be:
Is the number 2000 between 1 and 1000? false
Referenced Code:
import javax.swing.JOptionPane;
+1pt +2pt +1pt
public class TrueOrFalse { /**Main method*/
public static void main(String[] args) { // Prompt the user to enter an integer
String intString = JOptionPane.showInputDialog( \
// Convert string to int
int number = Integer.parseInt(intString);
// Display results
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+2pt
System.out.println(\the number \+ number + \between 1 and
1000 \ +2pts } }
2. (15pts) Write a program that reads the sales amount from the console and computes sales
commissions using the following scheme:
Sales Amount $0.01–$5,000
Commission Rate 8 percent 10 percent
12 percent
$5,000.01–$10,000
$10,000.01 and above
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Referenced Code:
import java.util.Scanner;
public class SalesCommissions {
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/**Main method*/
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in); // Prompt the user to enter sales amount System.out.println(\ double salesAmount = scanner.nextDouble();
// Compute sales commission double salesCommission = 0;
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if (salesAmount <= 5000)
salesCommission = salesAmount * 0.08;
else if (salesAmount <= 10000)
salesCommission = 5000 * 0.08 + (salesAmount - 5000) * 0.1;
+2pt else
salesCommission = 5000 * 0.08 + 10000 * 0.1 +
(salesAmount - 10000) * 0.12; +2pt
// Display results
System.out.println(\\salesCommission + \ } }
3. (10pts) By using a loop structure, write a program that computes
12?23?34?...?9899?99100 +1pt
Referenced Code:
import javax.swing.JOptionPane;
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public class LoopStructure{ /**Main method*/
public static void main(String[] args) { double sum = 0;
for (int i = 1; i <= 99; i++) sum += i * 1.0 / (i + 1);
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// Display results
System.out.println(\ } }
4. (10pts) By using a loop structure, write a program that displays the following pattern.
12345678987654321 234567898765432 3456789876543 45678987654 567898765 6789876 78987 898 9
+1pt
Referenced Code:
public class hello{
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/**Main method*/
public static void main(String[] args) {
for (int row = 1; row <= 9; row++) { // Print spaces
for (int column = 1; column < row; column++) System.out.print(\
for (int column = row; column <= 9; column++) System.out.print(column);
for (int column = 8; column >= row; column--) System.out.print(column);
System.out.println(); } } }
+2pt
+2pt
5. (8pts) Write a method that will return the sum of all digits in an integer. For example,
sum(1234) returns 10 and sum(12345) returns 15. The method signature is as follows:
public static int sum(int number)
Referenced Code:
public static int sum(int number) {
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+1pt