using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

​

namespace Projecttest

{

class Program

{

//Declare student structure

struct student

​

{

public string stnumber;

​

public string stname;

​

public string sex;

​

public float quizz1;

​

public float quizz2;

​

public float assigment;

​

public float midterm;

​

public float final;

​

public float total;

​

​

};

​

//main method

static void Main(string[] args)

{

​

try

{

student[] st = new student[20]; //create an array to store only 20 students'records for testing.

int itemcount = 0;

//show menu

displaymenu();

int yourchoice;

string confirm;

​

do

{

​

Console.Write("Enter your choice(1-8):");

​

yourchoice = int.Parse(Console.ReadLine());

​

​

switch (yourchoice)

{

​

case 1:add(st, ref itemcount); break;

case 2:delete(st, ref itemcount); break;

case 3:update(st, itemcount); break;

case 4:viewall(st, itemcount); break;

case 5:average(st, itemcount ); break;

case 6:showmax(st, itemcount); break;

case 7:showmin(st, itemcount); break;

case 8:find(st, itemcount); break;

case 9: bubblesort (st, itemcount); break;

​

default: Console.WriteLine("invalid"); break;

​

}

​

​

​

Console.Write("Press y or Y to continue:");

​

confirm = Console.ReadLine().ToString();

​

} while (confirm == "y" || confirm == "Y");

​

​

​

}

catch (FormatException f) { Console.WriteLine("Invalid input"); }

​

​

///////////////

​

Console.ReadLine();

​

}

​

​

//Menu contruction

​

static void displaymenu(){

​

Console.WriteLine("=====================================================");

​

Console.WriteLine(" MENU ");

​

Console.WriteLine("=====================================================");

​

Console.WriteLine(" 1.Add student records");

Console.WriteLine(" 2.Delete student records");

Console.WriteLine(" 3.Update student records");

Console.WriteLine(" 4.View all student records");

Console.WriteLine(" 5.Calculate an average of a selected student's scores");

Console.WriteLine(" 6.Show student who get the max total score");

Console.WriteLine(" 7.Show student who get the min total score");

Console.WriteLine(" 8.Find a student by ID");

Console.WriteLine(" 9.Sort students by TOTAL");

​

​

​

}

//method add/append a new record

static void add(student[] st,ref int itemcount){

​

Again:

Console.WriteLine();

Console.Write("Enter student's ID:");

st[itemcount].stnumber=Console.ReadLine().ToString() ;

​

if(search(st,st[itemcount].stnumber,itemcount)!=-1){

​

Console.WriteLine("This ID already exists.");

goto Again;

​

}

​

​

Console.Write("Enter student's Name:");

​

st[itemcount].stname=Console.ReadLine ().ToString();

​

​

Console.Write("Enter student's Sex(F or M):");

st[itemcount].sex=Console.ReadLine().ToString();

​

​

Console.Write("Enter student's quizz1 score:");

st[itemcount].quizz1=float.Parse(Console.ReadLine());

​

​

Console.Write("Enter student's quizz2 score:");

st[itemcount].quizz2=float.Parse(Console.ReadLine());

​

​

Console.Write("Enter student's assigment score:");

st[itemcount].assigment=float.Parse(Console.ReadLine());

​

​

Console.Write("Enter student's mid term score:");

st[itemcount].midterm=float.Parse(Console.ReadLine());

​

Console.Write("Enter student's final score:");

st[itemcount].final=float.Parse(Console.ReadLine());

​

st[itemcount].total=st[itemcount].quizz1+st[itemcount].quizz2+st[itemcount].assigment+st[itemcount].midterm+st[itemcount].final;

​

​

​

++itemcount;

​

​

​

}

//method to search for the location of the target record

static int search(student[] st, string id,int itemcount){

int found =-1;

for (int i = 0; i < itemcount && found==-1; i++)

{

​

if (st[i].stnumber == id) found=i;

​

else found=-1 ;

}

​

return found;

​

}

//method display all students' records

static void viewall(student[] st,int itemcount)

{

​

int i = 0;

​

Console.WriteLine("{0,-5}{1,-20}{2,-5}{3,-5}{4,-5}{5,-5}{6,-5}{7,-5}{8}(column index)", "0", "1", "2", "3", "4", "5", "6", "7", "8");

Console.WriteLine("{0,-5}{1,-20}{2,-5}{3,-5}{4,-5}{5,-5}{6,-5}{7,-5}{8,-5}", "ID", "NAME", "SEX", "Q1", "Q2", "As", "Mi", "Fi", "TOTAL");

​

Console.WriteLine("=====================================================");

​

while (i < itemcount)

{

​

if (st[i].stnumber !=null )

{

​

Console.Write("{0,-5}{1,-20}{2,-5}", st[i].stnumber, st[i].stname, st[i].sex);

​

Console.Write("{0,-5}{1,-5}{2,-5}",st[i].quizz1,st[i].quizz2,st[i].assigment);

​

Console.Write("{0,-5}{1,-5}{2,-5}",st[i].midterm,st[i].final,st[i].total);

​

Console.Write("\n");

}

​

i = i + 1;

​

​

​

}

​

}

​

​

​

// method to elete record

​

static void delete(student[] st, ref int itemcount)

{

string id;

int index;

if (itemcount > 0)

{

Console.Write("Enter student's ID:");

id = Console.ReadLine();

index = search(st, id.ToString(),itemcount);

​

if ((index!=-1) && (itemcount != 0))

{

if (index == (itemcount-1)) //delete the last record

{

​

clean(st, index);

--itemcount;

​

Console.WriteLine("The record was deleted.");

}

else //delete the first or middle record

{

for (int i = index; i < itemcount-1; i++)

{

st[i] = st[i + 1];

clean(st, itemcount);

--itemcount ;

}

​

}

​

}

else Console.WriteLine("The record doesn't exist.Check the ID and try again.");

​

​

}

else Console.WriteLine("No record to delete");

}

​

//method ot update record

​

static void update(student[] st, int itemcount)

{

string id;

int column_index;

Console.Write("Enter student's ID:");

id=Console.ReadLine();

Console.Write("Which field you want to update(1-7)?:");

column_index=int.Parse(Console.ReadLine());

​

int index = search(st, id.ToString(),itemcount);

​

if ((index != -1) && (itemcount != 0))

{

if (column_index == 1)

{

Console.Write("Enter student's Name:");

​

st[index].stname = Console.ReadLine().ToString();

}

​

else if (column_index == 2)

{

Console.Write("Enter student's Sex(F or M):");

st[index].sex = Console.ReadLine().ToString();

}

else if (column_index == 3)

{

Console.Write("Enter student's quizz1 score:");

st[index].quizz1 = float.Parse(Console.ReadLine());

}

else if (column_index == 4)

{

Console.Write("Enter student's quizz2 score:");

st[index].quizz2 = float.Parse(Console.ReadLine());

}

else if (column_index == 5)

{

Console.Write("Enter student's assigment score:");

st[index].assigment = float.Parse(Console.ReadLine());

}

else if (column_index == 6)

{

Console.Write("Enter student's mid term score:");

st[index].midterm = float.Parse(Console.ReadLine());

}

else if (column_index == 7)

{

Console.Write("Enter student's final score:");

st[index].final = float.Parse(Console.ReadLine());

}

else Console.WriteLine("Invalid column index");

st[index].total = st[index].quizz1 + st[index].quizz2 + st[index].assigment + st[index].midterm + st[index].final;

​

​

}

else Console.WriteLine("The record deosn't exits.Check the ID and try again.");

​

}

​

​

//method to calculate average score

static void average(student[] st, int itemcount)

{

string id;

float avg=0;

Console.Write("Enter students'ID:");

id = Console.ReadLine();

int index = search(st, id.ToString(),itemcount);

if (index != -1 && itemcount>0)

{

st[index].total = st[index].quizz1 + st[index].quizz2 + st[index].assigment + st[index].midterm + st[index].final;

avg = st[index].total /5;

}

​

Console.WriteLine("The average score is {0}.", avg);

}

//method to show max total score

static void showmax(student[] st, int itemcount)

{

float max = st[0].total;

int index=0;

Console.WriteLine(itemcount);

if (itemcount >= 2)

{

​

for (int j = 0; j < itemcount-1; ++j)

if (max < st[j+1].total) {

max = st[j+1].total;

index = j+1;

​

}

​

​

}

​

else if (itemcount == 1)

{

index = 0;

max = st[0].total;

}

​

​

else Console.WriteLine("Not record found!");

​

if (index != -1) Console.WriteLine("The student with ID:{0} gets the highest score {1}.", st[index].stnumber, max);

​

​

}

//method to show min total score

static void showmin(student[] st, int itemcount)

{

​

float min = st[0].total;

int index = 0;

if (itemcount >= 2)

{

for (int j = 0; j < itemcount-1; ++j)

if (min > st[j+1].total)

{

min = st[j+1].total;

index = j+1;

​

}

​

​

​

}

​

else if (itemcount == 1)

{

index = 0;

min = st[0].total;

}

else Console.WriteLine("No record found!");

​

if (index != -1) Console.WriteLine("The student with ID:{0} gets the lowest score {1}.", st[index].stnumber, min);

​

​

}

//method to find record

static void find(student[] st, int itemcount)

{

string id;

Console.Write("Enter student's ID:");

id=Console.ReadLine();

​

int index=search(st,id.ToString(),itemcount);

if (index != -1)

{

Console.Write("{0,-5}{1,-20}{2,-5}", st[index].stnumber, st[index].stname, st[index].sex);

​

Console.Write("{0,-5}{1,-5}{2,-5}", st[index].quizz1, st[index].quizz2, st[index].assigment);

​

Console.Write("{0,-5}{1,-5}{2,-5}", st[index].midterm, st[index].final, st[index].total);

Console.WriteLine();

​

}

else Console.WriteLine("The record doesn't exits.");

​

}

​

​

//method to sort records by total score

static void bubblesort(student[] dataset, int n)

{

int i, j;

for (i = 0; i < n; i++)

for (j = n - 1; j > i; j--)

if (dataset[j].total < dataset[j - 1].total )

{

student temp = dataset[j];

dataset[j] = dataset[j - 1];

dataset[j - 1] = temp;

}

​

}

//method to clean deleted record

static void clean(student[] st,int index)

{

st[index].stnumber = null;

st[index].stname = null;

st[index].sex = null;

st[index].quizz1 = 0;

st[index].quizz2 = 0;

st[index].assigment = 0;

st[index].midterm = 0;

st[index].final = 0;

st[index].total = 0;

​

}

​

​

}

}