Source
윤성준
받는사람 나
48분 전세부정보
Lorne Balfe - "Nobel Prize" (from the National Geographic Television Series)

[code]
#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int arr[1000];
int sorted[1000];
void quick_sort(int first, int end)
{
	int i, pivot;
	i = pivot = first;
	int j = end;
	int temp;

	if(first < end)
	{
		while(i < j)
		{
			while(arr[i] <= arr[pivot] && i < end)
			{
				i++;
			}
			while(arr[j] > arr[pivot])
			{
				j--;
			}
			if(i < j)
			{
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
		temp = arr[pivot];
		arr[pivot] = arr[j];
		arr[j] = temp;
		quick_sort(first, j - 1);
		quick_sort(j + 1, end);
	}
}
void merge(int left, int right)
{
   int m = left;
   int first = left, second = (left + right) / 2 + 1;
   bool first_empty = false, second_empty = false;
   while (1)
   {
      if (second > right)
      {
         second_empty = true;
         break;
      }
      if (first > (left + right) / 2)
      {
         first_empty = true;
         break;
      }
      if (arr[first] < arr[second])
      {
         sorted[m++] = arr[first++];
      }
      else
      {
         sorted[m++] = arr[second++];
      }
   }
   if (second_empty == true)
   {
      for (int i = first; i <= (left + right) / 2; i++)
      {
         sorted[m++] = arr[i];
      }
   }
   else
   {

      for (int i = second; i<= right; i++)
	  {
        sorted[m++] = arr[i];
	  }
   }
   for (int i = left; i <= right; i++)
   {
      arr[i] = sorted[i];
   }
}
void merge_sort(int start, int end)
{
	if(start < end)
	{
		merge_sort(start , (start + end ) / 2);
		merge_sort((start + end) / 2 + 1, end);
		merge(start, end);
	}
}
void selection_sort()
{
	int temp;
	for(int i = 0 ; i < 1000; i++)
	{
		for(int j = i + 1; j < 1000; j++)
		{
			if(arr[i] < arr[j])
			{
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
	}
}
int main(void)
{
	srand(time(NULL));
	double sum = 0;
	time_t start, end;
	long long int quick_sort_count = 0, merge_sort_count = 0, selection_sort_count = 0;
	for(int k = 0 ; k < 10 ; k++)
	{
		while(sum <= 10000)
		{
			for(int i = 0; i < 1000; i++)
			{
				arr[i] = (rand()%1000 + 1);
			}
			start = clock();
			quick_sort(0, 999);
			end = clock();
			sum += (double)(end - start);
			quick_sort_count++;
		}
		sum = 0;
		while(sum <= 10000)
		{
			for(int i = 0; i < 1000; i++)
			{
				arr[i] = (rand()%1000 + 1);
			}
			start = clock();
			merge_sort(0, 999);
			end = clock();
			sum += (double)(end - start);
			merge_sort_count++;
		}
		sum = 0;
		while(sum <= 10000)
		{
			for(int i = 0; i < 1000; i++)
			{
				arr[i] = (rand()%1000 + 1);
			}
			start = clock();
			selection_sort();
			end = clock();
			sum += (double)(end - start);
			selection_sort_count++;
		}
		sum = 0;
		printf("quick sort : %lld / merge_sort : %lld / selection_sort : %lld\n", quick_sort_count, merge_sort_count, selection_sort);
		quick_sort_count = merge_sort_count = selection_sort_count = 0;
	}
	return 0;
}
[/code]