카운팅 소트 설명.
http://en.wikipedia.org/wiki/Counting_sort
역시 C언어로 간단하게 구현해 보았다.
//# counting sort.
#include <stdio.h>
#define MAXLEN 10
void main()
{
int Data[MAXLEN] = {8, 1, 3, 2, 9, 9, 7, 10, 5, 2}; // item is 1 <= N <= 10
int ret[MAXLEN] = { 0, };
int count[MAXLEN];
int idx = 0;
//init count index
for (int i = 0; i <= MAXLEN; i++)
count[i] = 0;
for (int i = 0; i < MAXLEN; i++)
{
count[Data[i]] += 1;
}
idx = MAXLEN - 1;
for (int i = MAXLEN; i > 0; i--)
{
while (count[i] > 0)
{
ret[idx--] = i;
count[i] -= 1;
}
}
printf("{");
for (int i = 0; i < MAXLEN; i++)
{
printf("%d,", ret[i]);
}
printf("}\n");
}
