Exporting text to .txt file in C

Question

My program doesn't export anything to the .txt file; actually, I can't even compile it in this form.

#include <stdio.h>

typedef struct                        /*We define structure type to save memory
                                      ( im not sure about this!!!)   */
{
        char name[20];
        int num;
        } cont;

void input(cont a[],int n)              /*With this function i enter data in main program.*/
{
     int i;
     for(i=0;i<n;i++)
     {
                     printf("Insert name:");
                     scanf("%s",&a[i].name);
                     printf("Insert number:");
                     scanf("%d",&a[i].num);
                     printf("\n\n\n");
                     }
                     }

void export(cont a[],int n)       /*Export data that is entered in main program to text file
                                  output.txt that is in same folder as program*/
{
     FILE *text;
     int i;
     text=fopen("output.txt","w");
     fprintf(text,"Name:%s\nNumber:%d\n",a[i].name,a[i].num);
     fclose(text);
     }

void printinprog(cont a[],int n)          /*This just prints data in program so we can check
                                          that program works correctly.*/
{
     int i;
     for(i=0;i<n;i++)
     {
                     printf("Name:%s   Number:%d",a[i].name,a[i].num);
                     printf("\n\n");
                     }
                     }
main()
{
      cont per[20];
      int c; 
      printf("Enter number of contacts:");            
      scanf("%d",&c);
      input(per,c);                            
      export(per,c);
      system("pause");
      }

So when i move main part of export function to printinprog function it looks like this:

#include <stdio.h>

typedef struct                        /*We define structure type to save memory
                                      ( im not sure about this!!!)   */
{
        char name[20];
        int num;
        } cont;

void input(cont a[],int n)              /*With this function i enter data in main program.*/
{
     int i;
     for(i=0;i<n;i++)
     {
                     printf("Insert name:");
                     scanf("%s",&a[i].name);
                     printf("Insert number:");
                     scanf("%d",&a[i].num);
                     printf("\n\n\n");
                     }
                     }





void printinprog(cont a[],int n)          /*This just prints data in program so we can check
                                          that program works correctly.*/
{
     int i;
     for(i=0;i<n;i++)
     {
                     printf("Name:%s   Number:%d",a[i].name,a[i].num);
                     printf("\n\n");
                     }
     FILE *text;
     text=fopen("output.txt","w");
     fprintf(text,"Name:%s\nNumber:%d\n",a[i].name,a[i].num);
     fclose(text);
     }


main()
{
      cont per[20];
      int c; 
      printf("Enter number of contacts:");            
      scanf("%d",&c);
      input(per,c);                            
      printinprog(per,c);
      system("pause");
      }

Now program works but i get wrong data in .txt file and that looks like this.

So i am pretty sure that problem is in typedef struct actually i think there is a problem with data types cuz i define it like cont and that doesnt actually exist so proggram doesnt see that as a text data and the gives wrong data to .txt file.

Answer 1

Problem is that

 FILE *text;
 text=fopen("output.txt","w");
 fprintf(text,"Name:%s\nNumber:%d\n",a[i].name,a[i].num);
 fclose(text);

should be inside the loop, and it's outside it. What's happening is that it uses the last value for i (n) and is essentially printing from random memory locations....