Loop depending on user input

[firstlast]

EDIT:

I'm trying to get this program to loop the number of times I get it to input. The program compiles alright, and it does loop when I tell it too, but how do I output the grades of the multiple students?

#include <fstream>
#include <iostream>
#include <iomanip>
#include <string>
#include <cstdlib>

int weighted1 = 0;
int weighted2 = 0;
int weighted3 = 0;
int weighted4 = 0;
int weighted_average = 0;

const int MAX = 20;

int flag = 0;
int choice;
double sum = 0;
double average = 0;
char name [10];
char letter;
char file [MAX];

int num = 0;
int count = 0;

int main( )
{
std::ifstream in_stream;
std::ofstream out_stream;

in_stream.open("grade.txt");
out_stream.open("finalgrade.dat");

double first, second, third, fourth, fifth;
in_stream >> first >> second >> third >> fourth >> fifth;
//std::cout >> " 1: " >> first >> " 2: " >> second >> 
double grade = 0.0;
	grade = (first + second + third + fourth)/4;
	//this computes the name
//output 

bool menu = true;
while (menu != false)
{
    std::cout << "Would you like to open as keyboard or file?" << '\n';
	std::cout << "1. keyboard" << '\n';
	std::cout << "2. file" << '\n';

	std::cin >> choice;

	switch (choice)
{
case 1:
std::cout << "How many students? ";
	std::cin >> num;
	for(count =0; count < num; count++)	
	{
		{
		std::cout << "Student's Name: ";
		std::cin >> name;
		}
	do
{
	flag = 0;
	std::cout << "Please input your first exam grade and press enter: \n";
		std::cin >> first;
		if ((first < 0) || (first > 100))

		{
			std::cout << "You've entered invalid data!" << '\n';
			flag = 1;
		}
}while (flag == 1);

do
{
	flag = 0;
	std::cout << "Please input your second exam grade and press enter: \n";
		std::cin >> second;
		if ((second < 0) || (second > 100))

		{
			std::cout << "You've entered invalid data!" << '\n';
			flag = 1;
		}
}while (flag == 1);

do
{
	flag = 0;
	std::cout << "Please input your third exam grade and press enter: \n";
		std::cin >> third;
		if ((third < 0) || (third > 100))

		{
			std::cout << "You've entered invalid data!" << '\n';
			flag = 1;
		}
}while (flag == 1);

do
{
	flag = 0;
	std::cout << "Please input your final exam grade and press enter: \n";
		std::cin >> fourth;
		if ((fourth < 0) || (fourth > 100))

		{
			std::cout << "You've entered invalid data!" << '\n';
			flag = 1;
		}
		
}while (flag == 1);


grade = (first + second + third + fourth)/4;
sum = first + second + third + fourth;
average = sum/4;
	
	
//Letter grade and it's weighted averages
 letter = 'A';
 letter = 'B';
 letter = 'C';
 letter = 'D';
 letter = 'F';
 
 if(grade >= 90)
 { 
	 letter = ('A');
	 std::cout<<letter<<'\n';
 }
 else if(grade >= 80)
 {
	 letter = ('B');
	 std::cout<<letter<<'\n';
 }
 else if(grade >= 70)
 {
	 letter = ('C');
	 std::cout<<letter<<'\n';
 }
 else if(grade >= 60)
 {
	 letter = ('D');
	 std::cout<<letter<<'\n';
 }
 else if (grade < 60)
 {
	 letter = ('F');
	 std::cout<<letter<<'\n';
 }
 weighted1 = (first  * .20);
 weighted2 = (second * .20);
 weighted3 = (third  * .20);
 weighted4 = (fourth * .40);
 weighted_average = (weighted1 + weighted2 + weighted3 + weighted4);

 std::cout << "Exam Grades: " <<  first << "," << second << "," << third << "," << fourth << '\n';
 std::cout << "This is the average for " << name << ": " << weighted_average << '\n';
 std::cout << "This is the letter grade: " << letter << '\n';
  }
  {
  for(count =0; count < num; count++)	
  {
		std::ofstream myfile;
        myfile.open ("grades.txt");
        myfile << "Writing this to a file.\n";
		myfile << name << '\n';
        myfile << weighted_average << '\n';
		myfile << letter << '\n';
        myfile.close();
		
  }
  break;
  }


case 2:

in_stream.open("grade.txt");
out_stream.open("finalgrade.dat");

double first, second, third, fourth;
in_stream >> first >> second >> third >> fourth;
//std::cout >> " 1: " >> first >> " 2: " >> second >> 
double grade = 0.0;
	grade = (first + second + third + fourth)/4;

 letter = 'A';
 letter = 'B';
 letter = 'C';
 letter = 'D';
 letter = 'F';

 if(grade >= 90)
 letter = ('A');

 else if(grade >= 80)
 letter = ('B');

 else if(grade >= 70)
 letter = ('C');

 else if(grade >= 60)
 letter = ('D');

 else if (grade < 60)
 letter = ('F');
 
 weighted1 = (first  * .20);
 weighted2 = (second * .20);
 weighted3 = (third  * .20);
 weighted4 = (fourth * .40);
 weighted_average = (weighted1 + weighted2 + weighted3 + weighted4);

	std::cout << "Enter file name: ";
	     std::cin >> file;
	if(file!="grade.txt")
	{
         std::cout << std::fixed << "The average grade for: " << name << '\n';
	     std::cout << "average in grade.txt is: "<< weighted_average << std::setprecision(2) << '\n';
	     std::cout << "and the letter grade is: " << letter << '\n'; 
	}
			

in_stream.close();
out_stream.close();
	}

system ("pause");
return 0;
}
}

[Dy7SLyTq]

firstly, when you call functions you shouldnt put the return type. secondly just get a number from the user and have another variable start at zero and count up to it

[Smac89]

Line 63 big NO! Recursion is already expensive enough, why call the entire program in the program itself?? Plus you didn't add a break after that call to main

[Dy7SLyTq]

good catch smac. @op: if you just do return (or if your deeply nested setjmp) it will return to the calling function, so you can just unwind

[firstlast]

I tried coming up with something like this, at the beginning of the "void keyboard" function, but now it won't recognize it.

 std::cout << "How many records would you like to input?" << '\n';
 std::cin >> records;
for (int input = 0; input < records; records ++) 
{
std::cin >> input;
std::cout << "You entered " << input << "times." << '\n';
}

[Dy7SLyTq]

a) its just keyboard not void keyboard
b) @smac: you dont need to have a break in a default. think about it for a sec im sure youll get it ;)
c) why is menu bool?
d) why are you upping records? its gonna be an infinite loop because it will always be greater than zero (unless they want to enter negative records)
e) where do you expect all of keyboards args to come from. you call keyboard(), but have keyboard(double, double, double, etc)
f) why are you using passed args for input? that makes no sense. and why are you testing doubles against ints?
g) why do you call get_from()? i see no function called get_from(). i think you mean get_file(). does your compiler really allow all of this?
h)why does getfile have those args? you call a function with no args

[firstlast]

a. When I did that, it gave me the "Error: too few arguments in function call"
c. Because it's supposed to start out with the menu.
d. Not sure why, my mistake there.
g. That's supposed to come later.

[Dy7SLyTq]

a) if you look at all of the other letters youll see why it says that.
c) yeah i see that its supposed to start with menu, but why does it return bool?

[firstlast]

I don't know. I just wanted it to return when the user finished inputting the first time. I edited my code, maybe it can answer those other questions.

[Dy7SLyTq]

is that edited piece above your actual code? if so you didnt listen to a word i said

[firstlast]

No, I just rewrote it a little.

[Dy7SLyTq]

well take care of all the things i said were wrong then repost it

[firstlast]

I rewrote a more simplistic version of the code I had before without all the arguments and double variables. Now the problem lies within writing all the students to grade.txt instead of just the last one I enter.