im trying to do a sort for the array structure records that i have entered...
so far i've tried to use a book to do the coding...but im lost.. can anyone tell me if im on the right track or where im going wrong!!!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>
void filewrite(void);
void fileprint(struct tuple *myDB);
void quicksort(struct tuple *myDB,FILE *fp, int left, int right);
// Idea here is to enter an array of structures
// write them to disk and read them back
// simple structure
struct tuple {
char artist[50];
char album[50];
char label[50];
char year[4];
char type[30];
}cd;
/*********************************************************************************************************/
void filewrite(void) {
// file pointer
FILE *fp;
// structures
struct tuple myDB[3];
struct tuple otherDB[3];
// variable needed
int i;
i=1;
fp = fopen("mymusic.txt","wb");
while(i) {
printf("Enter the artist name: \n");
scanf("%s",myDB[i].artist);
printf("Enter the album: \n");
scanf("%s",myDB[i].album);
printf("Enter label name: \n");
scanf("%s",myDB[i].label);
printf("Enter year: \n");
scanf("%d",&myDB[i].year);
printf("Enter the type of music: \n");
scanf("%s",&myDB[i].type);
fprintf(fp, "%s %s %s %d %s\n",myDB[i].artist, myDB[i].album, myDB[i].label,myDB[i].year,myDB[i].type);
printf("\n\n press 1 to continue,0 to stop");
scanf("%d",&i);
}
// don't forget to close the file
fclose(fp);
}
/********************************************************************************************/
void quicksort(struct tuple *myDB,FILE *fp, int left, int right)
{
if((fp=fopen("mymusic.txt", "rb+")) ==NULL) {
printf("Cannot Open File For Read/Write.\n");
exit(1);
}
printf("Sorting disk file.\n");
quick_disk(fp, cd);
fclose(fp);
printf("List Sorted.\n");
}
/*A QuickSort For File.*/
void quick_disk(FILE *fp, int count)
{
qs_disk(fp, 0, count-1);
}
void qs_disk(FILE *fp, int left, int right)
{
int i,j;
char x[100];
i=left; j=right;
// strcpy(x, myDB[i].year(fp,(int)(i+j)/2));/*get the middle zip*/
do {
while(strcmp(myDB[i].year(fp,i),x)<0 && i<right) i++;
while(strcmp(myDB[i].year(fp,j),x)>0 && j>left) j--;
if(i<=j) {
swap_all_fields(fp, i, j);
i++; j--;
}
} while(i<=j);
if(left<j) qs_disk(fp, left, (int) j);
if(i<right) qs_disk(fp, (int) i, right);
}
void swap_all_fields(FILE *fp, int i, int j)
{
char a[sizeof(cd)], b[sizeof(cd)];
/*first read in record i and j */
fseek(fp, sizeof(cd)*i, SEEK_SET);
fread(a, sizeof(cd), 1, fp);
fseek(fp, sizeof(cd)*j, SEEK_SET);
fread(b, sizeof(cd), 1, fp);
/*then write them back in opposite slots*/
fseek(fp, sizeof(cd)*j, SEEK_SET);
fwrite(a, sizeof(cd), 1, fp);
fseek(fp, sizeof(cd)*i, SEEK_SET);
fwrite(b, sizeof(cd), 1, fp);
}
//*****************************************************************************************//
int main(void){
int c;
while(c!=6)
{
printf("GIVE CHOICE--\n");
printf(" 1 TO CD Information\n");
printf(" 2 TO Print Data On Screen\n");
printf(" 6 TO EXIT\n\n--");
scanf("%d",&c);
switch(c)
{
case 1:
filewrite();
break;
case 2:
quicksort();
break;
case 6:
break;
default:
break;
}
}
}Also will it be possible for me to add a critical count, analysis purposes to this sorting??
