Quick Sort in C

                                              To compile and execute the program, copy the code into a text file. Save the text file with the extinction .c (ex. program.c). Save your file in turboc2 or borland (it may your othe c-compiler). Now open you IDE (tc.exe) , goto file->pick file. Your source file will be loaded into IDE. Now you can compile and run the file easily.

#include"stdio.h" 
#include"conio.h" 
#define max 15 
int beg,end,top,i,n,loc,left,right; 
int array[max+1]; //contains the various elements. 
int upper[max-1],lower[max-1]; 
//two stacks to store two ends of the list. 

void main() 
{ 

void enter(void); 
void quick(void); 
void prnt(void); 
clrscr(); 
enter(); //entering elements in the array 
top=i-1; //set top to stack 
if (top==0) 
{ 
printf("UNDERFLOW CONDITION "); 
getch(); 
exit(); 
} 
top=0; 
if(n>1) 
{ 
top++; 
lower[top]=1;upper[top]=n; 
while ( top!=NULL ) 
{ 
beg=lower[top]; 
end=upper[top]; 
top--; 
left=beg; 
right=end; 
loc=beg; 
quick(); 
if ( beg { 
top++; 
lower[top]=beg; 
upper[top]=loc-1; 
} 
if(loc+1 { 
top++; 
lower[top]=loc+1; 
upper[top]=end; 
} 
} //end of while 
} //end of if statement 
printf("Sorted elements of the array are :"); 
prnt(); //to print the sorted array 
getch(); 
} //end of main 


void enter(void) 
{ 
printf("Enter the no of elements in the array:"); 
scanf("%d",&n); 
printf("Enter the elements of the array :"); 
for(i=1;i<=n;i++) 
{ 
printf("Enter the %d element :",i); 
scanf("%d",&array[i]); 
} 
} 


void prnt(void) 
{ 
for(i=1;i<=n;i++) 
{ 
printf("The %d element is : %d",i,array[i]); 
} 
} 

void quick() 
{ 
int temp; 
void tr_fr_right(void); 
while( array[loc]<=array[right] && loc!=right) 
{ 
right--; 
} 

if(loc==right) 
return ; 

if(array[loc]>array[right]) 
{ 
temp=array[loc]; 
array[loc]=array[right]; 
array[right]=temp; 
loc=right; 
tr_fr_right(); 
} 
return ; 
} 

void tr_fr_right() 
{ 
int temp; 
while( array[loc] > array[left] && loc!=left) 
{ 
left++; 
} 

if(loc==left) 
return ; 

if(array[loc] < array[left]) 
{ 
temp=array[loc]; 
array[loc]=array[left]; 
array[left]=temp; 
loc=left; 
quick(); 
} 
return ; 
}