[ACM]sorting algotithm

Time Limit: 1000MS Memory Limit: 65535KB
Total Submissions: 143 Accepted: 28

Description:

One of the fundamental problems of computer science is ordering a list of items. There're a plethora of solutions to this problem ,known as sorting algorithms.
Some sorting algorithms are simple and intuitive ,such as the bubble sort.Others,suchas the heap sort are not so simple , but produce lightening-fast results.
In the following is a list of some sorting algorithms . Of course, i can't tell you how to implement them here. you must use your own knowledge.
Bubble sort
Heap sort
Insertion sort
Merge sort
...
My business here is to give you some numbers, and to sort them is your business. Attention, I want the smallest number at the top of the sorted list.

Input:

The input file will consit of series data sets.Each data set has two parts.The first part contains two non-negative integers,n(1..n..100000)and m(1..m..n),
representing the total of numbers you will get and interval of the output sorted list.The second part contains n positive integers.I am sure that each integer in
this part will be less than 2000,000,00.
The input is terminated by a line with two zeros.

Output:

For one data set, you should ouput several numberes in ONE line.After you get the sorted list,you should output the first number of each m numbers, and you
print exact ONE space between two adjacent numbers.And please make sure that should NOT be any blank line between outputs of two adjacent data set.

Sample Input:

8 2
3
5
7
1
8
6
4
2
0 0

Sample Output:

1 3 5 7

Hint:

Source:

GDCPC

这题也是一个大水题，没什么说的，直接qsort，代码如下：

#include <stdio.h>
#include <stdlib.h>
 
int data[100000];
int cmp(const void * a, const void * b)
{
    return *(int *)a - *(int *)b;
}
 
int main()
{
    int m, n, i;
    while(1)
    {
        scanf("%d%d", &n, &m);
        if(!n)
            break;
        for(i = 0; i < n; i ++)
            scanf("%d", &data[i]);
        qsort(data, n, sizeof(int), cmp);
        for(i = 0; i + m < n; i += m)
            printf("%d ", data[i]);
        if(i < n)
            printf("%d
", data[i]);
    }
    return 0;
}