Question

in java by using the loop

1. Write a program that finds all students who score the highest and lowest average marks of the first two homework in CS (I). Your program should read the data from a file called "hw2.dat" and displays the output to another file called “hw2.out” and on the screen. The first line of the input file contains the number of students, N. The next N lines contain information about the students. Each data line contains student name and his/her marks. The output should display all student names, marks, and grades. In addition the highest and lowest marks and those who earned them along with the average and the grade of the class should be displayed.

If your input file contains:

20

Ali   Al-Shikeli                                    21          18     

Noora Al-Wardi                                 22          14

Aisha   Al-Rabani                               24          26

Ruqaya   Al-Moqbali                         20          28

Karima   Al-Rawas                             23          20

Manal Al-Siyabi                                18          28

Khalsa    Al-Sariri                               28          29

Iman   Al-Zadjali                                25          29

Farha Al-Waheibi                             20          27

Amel   Muqabal                                 21          20

Munira Alabri                                    20          28

Amel Khamis                                      21          13

Huda Al-Mukheini                             23          23

Nawal    Al-Shikeili                            25          29

Rasha Al-Raidan                               20          28

Saif Al-Hashmi                                  22          26

Mohamed Al-Kharousi                      26.5       21.5

Mohammed Al-Badi                          19          25

Ibrahim    Al-Mamari                        25          15

Ishaq   Al-malki                                  29          19

Then your output should look like:

Student Name                    Mark1                 Mark2                  Avg. Mark            Grade

--------------------------------------------------------------------------------------------------------------------

Ali   Al-Shikeli                     21.00                    18.00                    19.50                    D

Noorai Al-Wardi                 22.00                    14.00                    18.00                    D

Aisha   Al-Rabani                24.00                    26.00                    25.00                    B

---------------------                  ------                      ------                      ------                      --

---------------------                  ------                      ------                      ------                      --

Ishaq   Al-malki                  29.00                    19.00                    24.00                    B

The Maximum average mark is:      28.50 Scored by : Khalsa    Al-Sariri      

The minimum average mark is:       17.00 Scored by : Amel Khamis         

The average of the class:   22.98

The Grade of the class: C

Assign grades as follows: A: [27-30], B:[24-27[, C:[21-24[, D:[18-21[, F[0-18[

Answer 1

import java.io.*;
import java.util.*;
class Demo
{
public static void main(String agrs[]) throws Exception
{
FileReader fr=new FileReader("F:\\Haritha\\hw2.dat");
File nf=new File("F:\\Haritha\\hw2out");
FileWriter fw=new FileWriter(nf);
BufferedWriter bw=new BufferedWriter(fw);
Scanner sc=new Scanner(fr);
sc.nextLine();
bw.write("\nName \t Mark1 \t Mark2 \t Average \t Grade");
float min=0;
String mins="";
String maxs="";
float max=0;
while(sc.hasNextLine())
{
String line=sc.nextLine();
String cols[]=line.split(" ");
String m1=cols[2];
String m2=cols[3];
float a=Float.valueOf(m1);
float b=Float.valueOf(m2);
float per=(a+b)/2;
if(per<min)
min=per;
if(per>max)
max=per;
String avg=String.valueOf(per);
mins=String.valueOf(min);
maxs=String.valueOf(max);
String grd;
if(per>=27 && per<30)
grd="A";
else if(per>=24 && per<27)
grd="B";
else if(per>=21 && per<24)
grd="C";
else if(per>=18 && per<21)
grd="D";
else grd="F";
StringBuffer sb=new StringBuffer();
sb.append(cols[0]);
sb.append("\t");
sb.append(cols[1]);
sb.append("\t");
sb.append(cols[2]);
sb.append("\t");
sb.append(cols[3]);
sb.append("\t");
sb.append(avg);
sb.append("\t");
sb.append(grd);
String record=sb.toString();
bw.write(record);
bw.newLine();
}
bw.write("The Minimum average mark is:");
bw.write(mins);
bw.write("The Maximum average mark is:");
bw.write(maxs);
bw.newLine();
}
}