COMP 249 Programming Methodology II Sample midterm examination 2024 with complete solution

Programming Methodology II Sample midterm examination comp249


1) One-dimension arrays.

 What is the output of the following code?
int[] numbers = new int[10];
for(int i=0; i < numbers.length; ++i)
numbers[i] = i * 2;
for(int i=0; i < numbers.length; ++i)
System.out.print(numbers[i] / 2 + "
");
System.out.println();

 Answer : 0 1 2 3 4 5 6 7 8 9

2) Two-dimension arrays

 Show the output produced by the following java code.
int i, j, k, temp; // i and j are indices for the rows and
columns int [ ] [ ] A = { {5, 16, 7, 23, 15,} // 2-
dimension array
{31, 12, 22, 4, 19,}
{41, 21, 14, 37, 8 } };

…
for (i = 0; i < A.length; i++)
{
for (j = 0; j < A[i].length - 1; j++)
{
k = j + 1;
while (k < 5)
{
if (A[i] [k] < A[i] [j])
{
temp = A[i] [k];
A[[i] [k] = A[i] [j];
A[i] [j] = temp;
}
k = k + 1;
}
System.out.print(“ “ + array[i] [j]);
}
System.out.println(“\n”);
}
…

, Programming Methodology II Sample midterm examination comp249


 Answer :

5 7 15 16 23
4 12 19 22 31
8 14 21 37 41

3) File I/O and Exceptions.

 Write a main class that processes an input grade file (say grade.dat) storing the
student names, the student ids, the results for the 4 assignments (5% each), the
midterm test (30%), and final examination (50%) for each student. You have to
calculate the final grade out of 100 for each student and display in an output file (say
finalgrade.dat) the student names, the student ids and the final grade. In addition,
you must display on the screen the information for all students that fail.
Also, you must account for all possible exceptions that may be thrown when opening
the files.

Answer :

import java.util.Scanner;
import java.io.FileInputStream;
import java.io.PrintWriter;
import java.io.FileOutputStream;
import java.io.FileNotFoundException;
import java.util.InputMismatchException;

public class SampleDemo
{
public static void main(String[] args)
{
String name, id;
double a1, a2, a3, a4, midterm, final, total;

System.out.println("Processing grade file …");
Scanner inputStream = null;
try
{
inputStream = new Scanner(new
FileInputStream("grade.dat"));
}