SJF and SRTF scheduling algorithm

#include<stdio.h>
#include<conio.h>
#define n 20
main()
{
int d,p;
int b,i,n,bt[20],at[20],num;
int arr[20];
clrscr();
printf("ENTER THE NUMBER OF PROCESSES:  ");
scanf("%d",&n);
for(i=0;i<n;i++)
{
gotoxy(10,5);
printf("PROCESS: %d",i+1);
gotoxy(25,5);
printf("BURST TIME :    ");
scanf("%d",&bt[d]);
gotoxy(50,5);
printf("ARRIVAL TIME :");
scanf("%d",&at[p]);
}
gotoxy(29,20);
printf("SELECT ALGORITHM");
gotoxy(29,25);
printf("\n[1] - SJF");
gotoxy(29,30);
printf("\n[2] - SRTF");
gotoxy(29,35);
printf("\n[3] - EXIT");
gotoxy(25,40);
printf("\nENTER CHOICE:");
scanf("%d",&num);
getch();
}


what is wrong with my code, i tried to run it but i cant come up with the scheduling algorithm