终于把常用的排序算法写完了，发下自己记录一下。
#include <stdio.h>
//------------------------------------------------------------
//交换函数
void swap(int *a,int *b)
{
int temp;
temp = *a;
*a=*b;
*b=temp;
}
//------------------------------------------------------------
//选择排序
//时间复杂度：O(n^2)
int sort_select(int *a,int len)
{
int i,j;
int flag=0;
int temp=0;
for(i=0;i<len;i++)
{
temp=a[i];
flag = i;
for(j=i;j<len;j++)
{
if(a[j]<temp)
{
flag=j;
temp=a[j];
}
}
a[flag]=a[i];
a[i]=temp;
}
}
//------------------------------------------------------------
//直接插入排序
//时间复杂度：O(n^2)
int sort_insert(int *a,int len)
{
int i,j;
int temp;
for(i=1;i<len;i++)
{
temp=a[i];
for(j=i-1;j>=0;j--)
{
if(temp<a[j])
{
a[j+1] = a[j];
}
else
{
break;
}
}
a[j+1] = temp;
}
return 1;
}
//------------------------------------------------------------
//冒泡法排序
//时间复杂度：O(n^2)
int sort_bubbling(int *a,int len)
{
int i,j;
int temp;
for(i=1;i<len-1;i++)
{
for(j=0;j<len-i;j++)
{
if(a[j]>a[j+1])
{
temp = a[j];
a[j] = a[j+1];
a[j+1] = temp;
}
}
}
return 1;
}
//------------------------------------------------------------
//双向冒泡排序
//时间复杂度：O(n^2)
int sort_bubbling2(int *a,int len)
{
int j;
int left=1;
int right = len-1;
int t;
do{
//反向冒泡 从后往前
for(j=right;j>=left;j--)
{
if(a[j]<a[j-1])
{
swap(&a[j],&a[j-1]);
t =j;
}
}
//顺序冒泡 从前往后
left =t+1;
for(j=left;j<right;j++)
{
if(a[j]<a[j-1])
{
swap(&a[j],&a[j-1]);
t=j;
}
}
right = t-1;
}while(left<=right);
return 1;
}
//------------------------------------------------------------
//归并排序
//时间复杂度：O(nlogn)
void merge(int *a,int p,int q,int r)
{
int i,j;
int k;
int n1 = q-p+1;
int n2 = r-q;
int left[n1];
int right[n2];
for(i=0,k=p;i<n1;i++,k++)
left[i] = a[k];
for(i=0,k=q+1;i<n2;i++,k++)
right[i] = a[k];
for(i=0,j=0,k=p;i<n1&&j<n2;k++)
{
if(left[i]<right[j])
{
a[k] = left[i];
i++;
}
else
{
a[k] = right[j];
j++;
}
}
if(i<n1)
for(;i<n1;i++,k++)
a[k]=left[i];
if(j<n2)
for(;j<n2;j++,k++)
a[k] = right[j];
}
int mergesort(int *a,int p,int r)
{
int q;
if(p<r)
{
q=(p+r)/2;
mergesort(a,p,q);
mergesort(a,q+1,r);
merge(a,p,q,r);
}
}
int sort_merge(int *a,int len)
{
mergesort(a,0,len-1);
}
//------------------------------------------------------------
//快速排序
//时间复杂度：O(nlogn)
int quicksort(int *a,int l,int r)
{
int index;
int left =l;
int right = r;
if(l>=r)
return;
index = a[left];
while(left<right)
{
while(left<right && a[right]>index)
right--;
if(left<right)
a[left++] = a[right];
while(left<right && a[left]<index)
left++;
if(left<right)
a[right--] = a[left];
}
a[left] = index;
quicksort(a,l,left-1);
quicksort(a,left+1,r);
}
int sort_quick(int *a,int len)
{
quicksort(a,0,len-1);
}
//------------------------------------------------------------
//希尔排序
//时间复杂度：O(nlogn)
int sort_shell(int *a,int len)
{
int i,j;
int h;
int temp;
for(h=len/2;h>0;h=h/2)
{
for(i=h;i<len;i++)
{
temp = a[i];
for(j=i-h;j>=0;j-=h)
{
if(temp < a[j])
{
a[j+h] = a[j];
}
else
{
break;
}
}
a[j+h] = temp;
}
}
}
//------------------------------------------------------------
//堆排序
//时间复杂度：O(nlogn)
int heapmax(int *a,int i,int len)
{
int lchild=2*i;
int rchild=2*i+1;
int max=i;
if(i<=len/2)
{
if(lchild<=len && a[lchild-1]>a[max-1])
{
max = lchild;
}
if(rchild<=len && a[rchild-1]>a[max-1])
{
max = rchild;
}
if(max != i)
{
swap(&a[i-1],&a[max-1]);
heapmax(a,max,len);
}
}
}
int sort_heapmax(int *a,int len)
{
//create heap
int i;
for(i=len/2;i>=1;i--)
{
heapmax(a,i,len);
}
//heap sort
for(i=len;i>1;i--)
{
swap(&a[0],&a[i-1]);
heapmax(a,1,i-1);
}
}
//测试用例
int main(void)
{
int a[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_select[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_insert[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_bubbling[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_bubbling2[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_merge[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_quick[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_shell[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int a_heap[] = {1,23,3,4,5,6,87,34,3,77,77,3,56,100};
int i;
int len = sizeof(a)/sizeof(a[0]);
printf("the originala data: \n");
for(i=0;i<len;i++)
printf("%d,",a[i]);
printf("\n");
printf("insert:\n");
sort_insert(a_insert,len);
for(i=0;i<len;i++)
printf("%d,",a_insert[i]);
printf("\n");
printf("select:\n");
sort_select(a_select,len);
for(i=0;i<len;i++)
printf("%d,",a_select[i]);
printf("\n");
printf("bubbling:\n");
sort_bubbling(a_bubbling,len);
for(i=0;i<len;i++)
printf("%d,",a_bubbling[i]);
printf("\n");
printf("bubbling2:\n");
sort_bubbling2(a_bubbling2,len);
for(i=0;i<len;i++)
printf("%d,",a_bubbling2[i]);
printf("\n");
printf("merge:\n");
sort_merge(a_merge,len);
for(i=0;i<len;i++)
printf("%d,",a_merge[i]);
printf("\n");
printf("quick:\n");
sort_quick(a_quick,len);
for(i=0;i<len;i++)
printf("%d,",a_quick[i]);
printf("\n");
printf("shell:\n");
sort_shell(a_shell,len);
for(i=0;i<len;i++)
printf("%d,",a_shell[i]);
printf("\n");
printf("heap:\n");
sort_heapmax(a_heap,len);
for(i=0;i<len;i++)
printf("%d,",a_heap[i]);
printf("\n");
}