day 10 lab

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

void swap(int *,int *);
void cs_sort(int *,int);
void bubblesort(int* ,int);
void quicksort(int *,int,int);
int partition(int *,int,int);

int main()
{
    int n,u,l,i,input;
        clock_t start,end;
        double total;

        printf("Enter number of elements:");
        scanf("%d",&n);
        printf("Enter range for generating numbers(lower bound-upper bound):");
        scanf("%d %d",&l,&u);

        int *array=(int *)malloc(sizeof(int)*n);

        srand((unsigned)time(NULL));
        for(i=0;i<n;i++)
            array[i]=l+rand()%(u-l);

        /*printf("Before sorting:\n");
        for(i=0;i<n;i++)
            printf("%d,",array[i]);*/

        printf("Enter your preference:\n1:bubblesort\n2:cocktail shaker sort\n3:quicksort\n");
        scanf("%d",&input);

        start=clock();
        switch(input){
            case 1:bubblesort(array,n);break;
            case 2:cs_sort(array,n);break;
            case 3:quicksort(array,0,n-1);break;
            default:printf("Wrong input");break;
        }
        end=clock();

        printf("Sorted array:\n");
        for(i=0;i<n;i++)
            printf("%d,",array[i]);

        total=(double)(end-start)/CLOCKS_PER_SEC;

        printf("\n\nTime taken: %lf seconds\n",total);

    return 0;
}

void swap(int *a,int *b){
    int temp;
    temp=*a;
    *a=*b;
    *b=temp;
}


void bubblesort(int *a,int n){
    int i,j;
   for (i=0;i<n-1;i++)
       for (j=0;j<n-i-1;j++){
           if (a[j]>a[j+1])
              swap(a+j,a+j+1);
       }
}


void cs_sort(int *a,int n){
    int i,swapped=1,start,end;
    start=0;
    end=n-1;
    while(swapped){
        swapped=0;
        for(i=start;i<end;i++){
            if(a[i]>a[i+1]){
                swap(a+i,a+i+1);
                swapped++;
            }
        }


        if(!swapped)
            break;

        end--;
        for(i=end;i>=start;i--){
            if(a[i]>a[i+1]){
                swap(a+i,a+i+1);
                swapped++;
            }
        }
        start++;
    }

}

void quicksort(int *a,int l,int r){
    if(l<r){
        int q=partition(a,l,r);
        quicksort(a,l,q-1);
        quicksort(a,q+1,r);
    }
}

int partition(int *a,int l,int r){
    int x=a[l];
    int i=l+1,j;

    for(j=l+1;j<=r;j++){
        if(a[j]<x){
            swap(a+i,a+j);
            i++;
        }
    }
    swap(a+l,a+i-1);
    return i-1;
}