I have a program that I am trying to write that will open a file named list.txt, this file will contain a num, a ID, and a string name on each line. This program will read list.txt file and sort ID numbers and print sorted ID with number and name to index.txt file. I wrote a program code and it's working...
Here is my list.txt
(num, ID, name)
0 3 AB
1 2 BC
2 28 DC
3 1 EF
4 13 BB
10 30 CC
11 23 FF
14 16 GG
After compiled this program sorted ID with number and name, print to index.txt and it should be:
(ID, num, name)
1 3 EF
2 1 BC
3 0 AB
13 4 BB
16 14 GG
23 11 FF
28 2 DC
30 10 CC
Here is my program code:
#include <stdio.h>
#include <conio.h>
#include <process.h>
#include <stdlib.h>
#include <string.h>
#define NUM_NUMBERS 9
typedef struct student
{
int num;
int id;
char name[100];
}end;
void update();
void Sort(student array[], int n);
void load_menu();
void add(end *e);
void search(end e);
void view(end e);
FILE *fp;
FILE *f1;
int main(int argc, char** argv)
{
load_menu();
return 0;
}
void update()
{
end st[15];
int sayi[NUM_NUMBERS], number, i=0, j=0;
fp=fopen("list.txt", "r");
if( fp == NULL )
{
printf("File is not found at add();\n");
exit(0);
}
while(!feof(fp))
{
fscanf(fp,"%d%d%s",&st[i].num,&st[i].id,st[i].name);
i++;
}
Sort(st, NUM_NUMBERS);
f1=fopen("index.txt", "w");
for(int i=0; i<NUM_NUMBERS;i++)
{
fprintf(f1, "%d %d %s\n", st[i].id, st[i].num, st[i].name);
}
}
void Sort(end array[], int n)
{
int Min;
for(int i=0; i<n-1;i++)
{
Min=i;
for(int j=i+1;j<n;j++)
{
if(array[j].id<array[Min].id)
{
Min=j;
}
}
end temp=array[i];
array[i]=array[Min];
array[Min]=temp;
}
}
void load_menu(void)
{
end e;
int choice;
do
{
printf("1. Find a record given its ID value \n");
printf("2. Add a new record to the file \n");
printf("3. View Records\n");
printf("4. Exit\n\n");
printf("Please choose one: ");
scanf("%d",&choice);
switch(choice)
{
case 1:
search(e);
break;
case 2: add(&e);
update();
break;
case 3: view(e);
break;
case 4: printf("Done.");
return;
break;
default: printf("Invalid choice\n");
}
}while (choice != 5);
system("cls");
}
void add(end *e)
{
int i=0;
system("cls");
fp = fopen ( "list.txt", "a" );
if( fp == NULL )
{
printf("File is not found at add();\n");
exit(0);
}
printf("\n-----Add a new record-----\n");
printf("Enter number: ");
scanf("%d", &e->num);
printf("\nEnter ID : ");
scanf("%d",&e->id);
printf("\nEnter name: ");
scanf("%s",e->name);
fscanf(fp,"%d %d %s\n\n",&e->num, &e->id, e->name);
fprintf(fp,"%d %d %s\n\n",e->num ,e->id, e->name);
fclose(fp);
return;
}
void search(end e)
{
int i=0;
int sid;
system("cls");
fp = fopen ("list.txt", "r");
if(fp==NULL)
{
printf("File is not found at search();");
}
printf("\n-----Search ID-----\n");
printf("\nEnter ID : ");
scanf("%d",&sid);
printf("\nNumber ID Name");
while(!feof(fp))
{
fscanf(fp,"%d %d %s", &e.num, &e.id, &e.name);
if(sid==e.id)
{
printf("\n%d %d %s",e.num ,e.id, e.name);
}
}
printf("\n\n");
fclose(fp);
}
void view(end e)
{
int i=0;
system("cls");
printf("\n-----list.txt-----\n");
fp = fopen("list.txt", "r");
if(fp == NULL)
{
printf("File is not found at view();\n");
exit(0);
}
printf("\nNumber ID Name");
printf("\n");
while(fscanf (fp, "%d %d %s ",&e.num, &e.id, &e.name) != EOF )
printf("\n%d %d %s",e.num ,e.id, e.name);
printf("\n\n");
printf("-----index.txt-----\n");
f1 = fopen("index.txt", "r");
if(fp == NULL)
{
printf("File is not found.\n");
exit(0);
}
printf("\nNumber ID Name");
printf("\n");
while(fscanf (f1, "%d %d %s ",&e.id, &e.num, &e.name) != EOF )
printf("\n%d %d %s",e.id ,e.num, e.name);
printf("\n\n");
fclose(fp);
fclose(f1);
return;
}
But I used only array so I need to dynamically allocate at array of struct to store the info. Still don't know how to use dynamically allocate (malloc). Could you please show me how to use dynamically with code? Thanks for helps. (Sorry for bad english.)