This program finds Kth smallest element in an unsorted array

kth_smallest.c

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

void swap(int *a, int *b){

    int temp = *a;
    *a = *b;
    *b = temp;

}
int partition(int A[], int start, int end){
    int i= start+1;
    int j = i;
    int pivot = start;
    for(; i<end; i++){
        if(A[i]<A[pivot]){
            swap(&A[i],&A[j]);
            j++;
        }
    }
    if(j<=end){
        swap(&A[pivot],&A[j-1]);
    }
    for(i=0;i<10;i++){
        printf("%d  ", A[i] );
    }
    printf("\n");
        return j-1;
}

void quick_sort(int A[], int start, int end, int K){
    int part ;
    if(start <end) {
        part  =  partition(A, start, end);
            if(part == K-1){
                printf("kth smallest element : %d" , A[part]);
            }
        if(part>K-1){
            quick_sort(A, start,part, K);
        }
        else{
            quick_sort(A, part+1, end, K);
        }
    }
    return;
}
/* Driver program for the function written above */
int main(){
    int array[] = {4,2,1,7,5,3,8,10,9,6};
    int n = sizeof(array)/sizeof(array[0]);
    quick_sort(array,0, n, 4);
    return 0;
}