从数组中寻找前k小的数据

#include<stdio.h>
void find_bigger_num(int *arr ,int iLeft ,int iRight ,int iTargetSize ){
        if( iLeft>= iRight) return;
        int iPivot = arr[ iLeft];
        int iBegin = iLeft;
        int iEnd = iRight;
        while (iBegin < iEnd) {
               while (iBegin < iEnd && arr[iEnd] >= iPivot) {
                     iEnd--;
              }
               arr[iBegin] = arr[iEnd];
               while (iBegin < iEnd && arr[iBegin] <= iPivot) {
                     iBegin++;
              }
               arr[iEnd] = arr[iBegin];
       }
        arr[iBegin] = iPivot; //iBegin == iEnd
       
        int iLeftPartNum = iBegin - iLeft;
        if(iLeftPartNum== iTargetSize || iLeftPartNum+1==iTargetSize )
               return;
        else if(iLeftPartNum> iTargetSize){
              find_bigger_num( arr, iLeft,iBegin-1, iTargetSize);
       }
        else if(iLeftPartNum+1< iTargetSize){
              find_bigger_num( arr,iBegin+1, iRight, iTargetSize-(iLeftPartNum+1));
       }
}

int main()
{
        int arr[] = {6,1,5,2,3,7,4,10,9,8};
        int iTargetSize = 6;
       find_bigger_num(arr,0, sizeof(arr)/ sizeof( int)-1,iTargetSize);
       
        for ( int iLoop = 0; iLoop < iTargetSize; iLoop++) {
              printf( "%d ",arr[iLoop]);
       }
       printf( "\n");
        return 0;
}