Thread: I dont know whats going on with my program

hey guys im supposed to do the program attached but it does not run how it is supposed to. Can i have some help in fixing this please.

Code:

#include <stdio.h>
#include <string.h>
#include <conio.h>


struct StudentData
{
    char name[25];
    double ID;
    int ELA, Math, Science;
};
    
struct StudentData Students[5];     //array to hold 5 StudentData structures
int reccount = 0;                //keeps count of number of records read in from file


void initStructs();
void printStudentData();    


int main()
{    
    initStructs();
    
    printStudentData();
}






void initStructs(){
    
    FILE * input;    //create file pointer
    int pos,ELA,Math,Science = 0;    //struct array pointer
    char n[25];        //to retrieve student name
    double ID;        //to retrieve student ID
    
    
    input = fopen("sdata.txt", "r");
    
    if(!input)
    {
        printf("Unable to open file\n"); //output if file could not be opened
    }
    
    while (fscanf(input,"%s %ID %ELA %Math %Science %lf",&n, &ID,&ELA,&Math,&Science) != EOF) 
    {
        //Read the data from each line into struct
        strcpy(Students[pos].name, n);
        Students[pos].ID = ID;
        Students [pos].ELA = ELA;
        Students [pos].Math=Math;
        Students [pos].Science=Science;
        
    
        reccount++;
        
        
        pos++;
    }
    
    printf("Finished reading from file...\n\n");
    
    fclose(input);    //close the file
    
}//end initStructs




/* printStudentData is a function that loops through the Students array 
 * prints the data in each student struct to screen 
 */
void printStudentData(){
    printf("Printing %d Records from file...\n\n", reccount);
    printf("Name\t\t  ID\t\t ELA\t\t Math\t\t Science\n");
    
    for(int i=0; i<reccount; i++){
        printf("%s \t\t\t %8.2lf\n", Students[i].name, Students[i].ID,Students[i].ELA,Students[i].Math,Students[i].Science);
    }
    printf("\n\nFinished printing records.\nPress a key to continue.\n");
    getch();
}

Hi davic01!

Here an example:
first student.h:

Code:

#ifndef STUDENT_INC_
#define STUDENT_INC_

#include <iostream>
#include <iomanip>
#include <stdlib.h>
#include <string.h>
#include <didi.h>

// Setze Vordergrundfarbe \x1b ist ESC 27
#define RED     "\x1b[31m"
#define GREEN   "\x1b[32m"
#define YELLOW  "\x1b[33m"
#define BLUE    "\x1b[34m"
#define MAGENTA "\x1b[35m"
#define CYAN    "\x1b[36m"

#define WHITE_GREEN "\x1b[1;32;47m"  // Backround = White, Foreground = Green  --> Vordergrund;Hintergrund
#define BLUE_YELLOW "\x1b[1;34;43m"  
#define WHITE_BLACK "\x1b[1;37;40m"  
#define BLACK_YELLOW "\x1b[1;30;43m"  
#define BLACK_WHITE "\x1b[1;30;47m"
#define BLUE_WHITE "\x1b[1;34;47m"
#define BLUE_GREEN "\x1b[1;34;42m"
#define BLACK_GREEN "\x1b[1;30;42m"

#define COLOR_RESET   "\x1b[0m"
 
 
int initStructs(char filename[], struct StudentData (*Students)[5]);
void printStudentData(struct StudentData (*Students)[5], int reccount);    
 

#endif

now student.cpp

Code:

#include "student.h"

int initStructs(char filename[], struct StudentData (*Students)[5])
{
     
    FILE * input;    //create file pointer
    int pos,ELA,Math,Science = 0;  // struct array pointer
    char n[25] = {0};              // to retrieve student name
    double ID;                     // to retrieve student ID
    int rewer = -1;    
 
    input = fopen(filename, "r");
     
    if(!input)
       {
        std::cout << "Unable to open file" << std::endl; //output if file could not be opened
        return rewer;
       }
         
    pos = 0; 
     
    while (fscanf(input,"%lf %s %d %d %d", &ID, n, &ELA, &Math, &Science) != EOF) 
    {
       //Read the data from each line into struct
        strcpy(Students[pos]->name, n);
        Students[pos]->ID = ID;
        Students[pos]->ELA = ELA;
        Students[pos]->Math = Math;
        Students[pos]->Science = Science;
         
         //printf("pos=%d %lf %s   %d   %d  %d\n",pos, ID, n, ELA, Math, Science);
         //printf("pos=%d %lf %s   %d   %d  %d\n",pos, Students[pos]->ID, Students[pos]->name, Students[pos]->ELA, Students[pos]->Math, Students[pos]->Science);
               
        pos++;
    }
     
   //for(int i=0; i< pos; i++)  printf("nr=%d %8.2lf\t %-20s\t%d\t%d\t%d\n", i, Students[i]->ID, Students[i]->name, Students[i]->ELA,Students[i]->Math,Students[i]->Science);
     
    std::cout << "Finished reading from file:" << std::endl << filename << std::endl;
    std::cout << "reccount: " << pos << std::endl; 
     
    fclose(input);    //close the file
    
 
return pos;    
}//end initStructs
 

/* printStudentData is a function that loops through the Students array 
 * prints the data in each student struct to screen 
 */
void printStudentData(struct StudentData (*Students)[5], int reccount)
{
    std::cout << "\n\nPrinting " << reccount << " Records from file..." << std::endl << std::endl;
    std::cout << " ID\t\t Name\t\t\tELA\tMath\tScience" << std::endl;
    std::cout << MAGENTA << "-----------------------------------------------------------------" << COLOR_RESET<< std::endl; 
    for(int i=0; i< reccount; i++)
    {
     std::cout << BLUE << std::left << std::setw(10) << Students[i]->ID;
     std::cout << WHITE_BLACK << "\t" << std::left << std::setw(20) << Students[i]->name << "\t";
     std::cout << CYAN << Students[i]->ELA << "\t" << WHITE_BLACK << Students[i]->Math << BLUE_WHITE << "\t" << Students[i]->Science << COLOR_RESET << std::endl;
    }
    std::cout << RED << "-----------------------------------------------------------------" << COLOR_RESET << std::endl; 
    std::cout << std::endl<< "Ende der Liste" << std::endl;
}

main.cpp:

Code:

#include "student.h"
  
  
 
int main(int argc, char **argv)
{    
 struct StudentData Students[5];     //array to hold 5 StudentData structures
 char finam[200] = {0};
 int reccount = 0;                //keeps count of number of records read in from file
   
  strcpy(finam, "test.txt");
 
  reccount = initStructs(finam, &Students);
  printStudentData(&Students, reccount);
  
return EXIT_SUCCESS;
}

here test.txt

Code:

1001 Janet  81 42 65
1002 John   47 68 72
1003 Jacob  92 94 87 
1004 Jill   96 88 89
1005 Jack   54 62 41

example output:


May be some guys think the colours are awful, so change it!

Sorry forgot didi.h:

Code:

#ifndef LI_H_
#define LI_H_ 2

extern struct StudentData
{
    char name[25];
    double ID;
    int ELA;
    int Math;
    int Science;
}Students;

#endif

Unneeded includes:

If somebody want to work with this example, they can delete it themself.
Otherwise it would be like someone wants to build a house and he don't know how to work with an screwdriver or a saw, hammer or a shovel.


I think to split code in more files, like headers makes it easier to work with it.

The direct use of numbers in the code shows here better how does it works.

Important here is by the function

"printStudentData"

You need to take call by reference to get the right values of the struct.
When you take call by value, you will get nonsens on screen.