Array not working

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This program is suppose to ask the user how many students how many grades then ask for student name and student grades then gather the information and display the name and the grade and the average and the total average for the class.
I have gotten this far but the last set of arrays is not working thanks for the help.

#include <iostream>
#include <string>
using namespace std;

int main(){

int numgrade;
int numstudent;
const int max_students = 499;
const int max_grade = 499;
string student [max_students];
int students [max_students][max_grade] = {0,0};
int grade;

cout << "Enter the number of students: ";
cin >> numstudent;

cout << "Enter the number of grades: ";
cin >> numgrade;
for (int curstudent =0; curstudent < numstudent; curstudent++){
	
	cout << "Enter the students name: ";
	cin >> student[curstudent];
    
	for (int curgrade =0; curgrade < numgrade; curgrade++){
        cout << "Enter the grade: ";
		cin >> student[curgrade];
	}
}

student [0] = 100;
student [1] = 75;
student [2] = 50;
student [3] = 25;

for (int curstudent =0; curstudent < numstudent; curstudent++){
		for (int curgrade =0; curgrade < numgrade; curgrade++){
       	cout << student [0] << endl;
		cout << student [1] << endl;
		cout << student [2] << endl;
		cout << student [3] << endl;
	}
}
system("pause");
return 0;
}

Posted 22-Oct-10 2:22am

EDITH GINGRAS

Updated 22-Oct-10 2:23am

Rajesh Anuhya

v2

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2 solutions

Solution 1

Well the logic is not correct..
whats happening with the first two set of for loops is that:

in the first loop :
for (int curstudent =0; curstudent < numstudent; curstudent++){

cout<< "Enter the students name: ";
cin >> student[curstudent];

here the value in the student array is being entered.

but in the second "for" loop,

again you are entering the values in the array starting from 0(the index),
so each time u loop the values that you entered from the first loop,it gets overwritten with values from the second loop.

So you have to change your logic!

Posted 22-Oct-10 2:56am

Tarun.K.S

Updated 22-Oct-10 3:29am

v3

Comments

Tarun.K.S 22-Oct-10 9:04am

i am not able to understand your question but i think you can use a 2-dimensional array to store the student name and his/her grades.

EDITH GINGRAS 22-Oct-10 9:10am

ok now I am confused what do you mean by logic and where are you speaking about the names and the grades and the num grades and the num student part of this is working fine its the other part that is not working that is the problem sorry I am not good at explaining what I needed the help with the problem begins when I try to get the name, grade and average in a table like format using the array. Or is this already there and all I need is to add the total average grade for student array to the print out and then just get the total average of the class array to print out the results? ok I think Im on to something here but I could be wrong thanks any more help on this is appreciated

William Winner 22-Oct-10 12:24pm

I like that...."what do you mean by logic?"

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CPallini · Accepted Answer · 2010-10-22T03:10:00

EDITH GINGRAS wrote:
string student [max_students];
int students [max_students][max_grade] = {0,0};

Warning: the variable 'students' has really a silly name ('grades' would be better, IMHO).

EDITH GINGRAS wrote:
for (int curstudent =0; curstudent < numstudent; curstudent++){

cout << "Enter the students name: ";
cin >> student[curstudent];

for (int curgrade =0; curgrade < numgrade; curgrade++){
cout << "Enter the grade: ";
cin >> student[curgrade];
}
}

Wrong, change to

for (int curstudent=0; curstudent < numstudent; curstudent++)
{
  cout << "Enter the students name: ";
  cin >> student[curstudent];
  for (int curgrade=0; curgrade < numgrade; curgrade++)
  {
    cout << "Enter the grade: ";
    cin >> students[curstudent][curgrade];
  }
}

EDITH GINGRAS wrote
:student [0] = 100;
student [1] = 75;
student [2] = 50;
student [3] = 25;

Wrong: remove such bogus lines.

EDITH GINGRAS wrote:
for (int curstudent =0; curstudent < numstudent; curstudent++){
for (int curgrade =0; curgrade < numgrade; curgrade++){
cout << student [0] << endl;
cout << student [1] << endl;
cout << student [2] << endl;
cout << student [3] << endl;
}
}

Wrong: change to

for (int curstudent=0; curstudent < numstudent; curstudent++)
{  
  cout << student [curstudent] << endl;
  for (int curgrade=0; curgrade < numgrade; curgrade++)
  {
     cout << students[curstudent][curgrade] << endl;   
  }
}

BTW why are you using fixed-size arrays, instead of, for instance, the std::vector class?
:)