Object Oriented Programming Lab 5
Questions
Question 1
Write a program (with series of functions) that reads student scores, gets the best score, and then assigns grades based on the following scheme:
- Grade is B if score is >= best - 20;
- Grade is C if score is >= best - 30;
- Grade is D if score is >= best - 40;
- Grade is F otherwise. The program prompts the user to enter the total number of students, then prompts the user to enter all of the scores, and concludes by displaying the grades. Here is a sample run:
import java.util.Scanner;
public class StudentScore {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Prompt the user to enter the number of students
System.out.print("Enter the number of students: ");
int numberOfStudents = input.nextInt();
// Create an array to hold the scores
int[] scores = new int[numberOfStudents];
// Prompt the user to enter each score
System.out.println("Enter the scores:");
for (int i = 0; i < numberOfStudents; i++) {
scores[i] = input.nextInt();
}
// Get the best score
int bestScore = getBestScore(scores);
// Display the grades
for (int i = 0; i < numberOfStudents; i++) {
char grade = getGrade(scores[i], bestScore);
System.out.println("Student " + i + " score is " + scores[i] + " and grade is " + grade);
}
input.close();
}
// Function to get the best score
public static int getBestScore(int[] scores) {
int best = scores[0];
for (int score : scores) {
if (score > best) {
best = score;
}
}
return best;
}
// Function to get the grade based on the score and best score
public static char getGrade(int score, int best) {
if (score >= best - 10) {
return 'A';
} else if (score >= best - 20) {
return 'B';
} else if (score >= best - 30) {
return 'C';
} else if (score >= best - 40) {
return 'D';
} else {
return 'F';
}
}
}
C:\Users\TJ\prog\temp\oop\lab5>java StudentScore.java
Enter the number of students: 4
Enter the scores:
90
100
50
60
Student 0 score is 90 and grade is A
Student 1 score is 100 and grade is A
Student 2 score is 50 and grade is F
Student 3 score is 60 and grade is DQuestion 2
Write a program (with series of functions) that reads in ten numbers and displays distinct numbers (i.e., if a number appears multiple times, it is displayed only once). Hint: Read a number and store it to an array if it is new. If the number is already in the array, ignore it. After the input, the array contains the distinct numbers. Here is the sample run of the program:
import java.util.Scanner;
public class Distinct {
public static void main(String[] args) {
int a[] = new int[10];
Scanner scanner = new Scanner(System.in);
for (int i = 0; i < a.length; i++) {
System.out.print("Enter a number: ");
a[i] = scanner.nextInt();
}
scanner.close();
int new_array[] = new int[10];
int new_array_index = 0;
for (int i = 0; i < a.length; i++) {
boolean isDistinct = true;
for (int j = 0; j < new_array_index; j++) {
if (a[i] == new_array[j]) {
isDistinct = false;
break;
}
}
if (isDistinct) {
new_array[new_array_index++] = a[i];
}
}
System.out.print("Distinct elements: ");
for (int i = 0; i < new_array_index; i++) {
System.out.print(new_array[i] + " ");
}
}
}C:\Users\TJ\prog\temp\oop\lab5>java Distinct.java
Enter a number: 4
Enter a number: 5
Enter a number: 6
Enter a number: 2
Enter a number: 3
Enter a number: 4
Enter a number: 5
Enter a number: 6
Enter a number: 7
Enter a number: 9
Distinct elements: 4 5 6 2 3 7 9Question 3
Write a program to create a Vector that holds the following values. 2, 6, Hello, 7, everyone Use appropriate methods of Vector class to perform the following task.
- Iterate through the vector
- Add element at a specified index
- Check whether a given element exist in the Vector, if so remove it
- Replace an item with a new value given
- Retrieve the first and the last element of the Vector
import java.util.Vector;
import java.util.Enumeration;
public class VectorExample {
public static void main(String[] args) {
// Create a Vector and add initial values
Vector<Object> vector = new Vector<>();
vector.add(2);
vector.add(6);
vector.add("Hello");
vector.add(7);
vector.add("everyone");
// a. Iterate through the vector
System.out.println("Iterating through the vector:");
Enumeration<Object> enumeration = vector.elements();
while (enumeration.hasMoreElements()) {
System.out.println(enumeration.nextElement());
}
// b. Add element at a specified index
vector.add(2, "newElement");
System.out.println("\nVector after adding element at index 2:");
System.out.println(vector);
// c. Check whether a given element exists in the Vector, if so remove it
Object elementToRemove = "Hello";
if (vector.contains(elementToRemove)) {
vector.remove(elementToRemove);
System.out.println("\nVector after removing element 'Hello':");
System.out.println(vector);
}
// d. Replace an item with a new value given
int indexToReplace = 3;
Object newValue = "newValue";
vector.set(indexToReplace, newValue);
System.out.println("\nVector after replacing element at index 3 with 'newValue':");
System.out.println(vector);
// e. Retrieve the first and the last element of the Vector
Object firstElement = vector.firstElement();
Object lastElement = vector.lastElement();
System.out.println("\nFirst element: " + firstElement);
System.out.println("Last element: " + lastElement);
}
}References
Information
- date: 2025.02.27
- time: 14:33