所谓的课内代码就是指，非课后习题代码，是给出的要背诵的代码，一共有：选择排序、插入排序、冒泡排序、归并排序、堆排序、快速排序。并给出测试样例。
冒泡排序
void BubbleSort(int a[],int n){
int i,j,flag;
int tmp;
for(i=n-1;i>=0;i--){
flag = 0;
for(j = 1;j<=i;j++){
if(a[j-1]>a[j]){
tmp = a[j];
a[j] = a[j-1];
a[j-1] = tmp;
flag = 1;
}
}
if(flag == 0)
return ;
}
}
调用的是
BubbleSort(a,6);//6是指0-5
选择排序
void InsertSort(int a[],int n){
int i,j;
int tmp;
for(i=0;i<n;i++){
tmp = a[i];
j = i-1;
while(j>=0 && tmp<a[j]){
a[j+1] = a[j];
--j;
}
a[j+1] = tmp;
}
}
调用的是
InsertSort(a,5);
快速排序
void QuickSort(int a[],int low,int high){
int tmp;
int i = low,j = high;
if(low<high){
tmp = a[low];
while(i<j){
while(j>i && a[j] >= tmp) j--;
if(i<j){
a[i] = a[j];
++i;
}
while(i<j && a[i] < tmp) ++i;
if(i<j){
a[j] = a[i];
--j;
}
}
a[i] = tmp;
QuickSort(a,low,i-1);
QuickSort(a,i+1,high);
}
}
调用的是
QuickSort(a,0,6);
选择排序
void SelectSort(int a[],int n){
int i,j,k;
int tmp;
for(i=0;i<n;i++){
k = i;
for(j=i+1;j<n;j++)
if(a[k] > a[j])
k = j;
tmp = a[i];
a[i] = a[k];
a[k] = tmp;
}
}
调用的是
SelectSort(a,5);
堆排序
void Sift(int a[],int low,int high){
int i = low,j = 2*i;
int tmp = a[i];
while(j<=high){
if(j<high && a[j] < a[j+1])
++j;
if(tmp<a[j]){
a[i] =a[j];
i = j;
j = 2*i;
}else
break;
}
a[i] = tmp;
}
void HeapSort(int a[],int n){
int i;
int tmp;
for(i=n/2;i>=1;i--)
Sift(a,i,n);
for(i=n;i>=2;--i){
tmp = a[1];
a[1] = a[i];
a[i] = tmp;
Sift(a,1,i-1);
}
}
调用的是
HeapSort(a,6);
归并排序
void Merge( int A[], int TmpA[], int L, int R, int RightEnd )
{
/* 将有序的A[L]~A[R-1]和A[R]~A[RightEnd]归并成一个有序序列 */
int LeftEnd, NumElements, Tmp;
int i;
LeftEnd = R - 1; /* 左边终点位置 */
Tmp = L; /* 有序序列的起始位置 */
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd ) {
if ( A[L] <= A[R] )
TmpA[Tmp++] = A[L++]; /* 将左边元素复制到TmpA */
else
TmpA[Tmp++] = A[R++]; /* 将右边元素复制到TmpA */
}
while( L <= LeftEnd )
TmpA[Tmp++] = A[L++]; /* 直接复制左边剩下的 */
while( R <= RightEnd )
TmpA[Tmp++] = A[R++]; /* 直接复制右边剩下的 */
for( i = 0; i < NumElements; i++, RightEnd -- )
A[RightEnd] = TmpA[RightEnd]; /* 将有序的TmpA[]复制回A[] */
}
void MergeSort(int a[],int low,int high){
if(low<high){
if(low<high){
int mid = (low+high)/2;
MergeSort(a,low,mid);
MergeSort(a,mid+1,high);
int b[6];
Merge(a,b,low,mid,high);
}
}
}
调用的是
MergeSort(a,0,6);
完整测试代码
#include<iostream>
using namespace std;
void Print(int a[],int n){
for(int i =0;i<n;i++)
cout << a[i] << " ";
cout << endl;
}
void BubbleSort(int a[],int n){
int i,j,flag;
int tmp;
for(i=n-1;i>=0;i--){
flag = 0;
for(j = 1;j<=i;j++){
if(a[j-1]>a[j]){
tmp = a[j];
a[j] = a[j-1];
a[j-1] = tmp;
flag = 1;
}
}
if(flag == 0)
return ;
}
}
void InsertSort(int a[],int n){
int i,j;
int tmp;
for(i=0;i<n;i++){
tmp = a[i];
j = i-1;
while(j>=0 && tmp<a[j]){
a[j+1] = a[j];
--j;
}
a[j+1] = tmp;
}
}
void QuickSort(int a[],int low,int high){
int tmp;
int i = low,j = high;
if(low<high){
tmp = a[low];
while(i<j){
while(j>i && a[j] >= tmp) j--;
if(i<j){
a[i] = a[j];
++i;
}
while(i<j && a[i] < tmp) ++i;
if(i<j){
a[j] = a[i];
--j;
}
}
a[i] = tmp;
QuickSort(a,low,i-1);
QuickSort(a,i+1,high);
}
}
void SelectSort(int a[],int n){
int i,j,k;
int tmp;
for(i=0;i<n;i++){
k = i;
for(j=i+1;j<n;j++)
if(a[k] > a[j])
k = j;
tmp = a[i];
a[i] = a[k];
a[k] = tmp;
}
}
void Sift(int a[],int low,int high){
int i = low,j = 2*i;
int tmp = a[i];
while(j<=high){
if(j<high && a[j] < a[j+1])
++j;
if(tmp<a[j]){
a[i] =a[j];
i = j;
j = 2*i;
}else
break;
}
a[i] = tmp;
}
void HeapSort(int a[],int n){
int i;
int tmp;
for(i=n/2;i>=1;i--)
Sift(a,i,n);
for(i=n;i>=2;--i){
tmp = a[1];
a[1] = a[i];
a[i] = tmp;
Sift(a,1,i-1);
}
}
void Merge( int A[], int TmpA[], int L, int R, int RightEnd )
{
/* 将有序的A[L]~A[R-1]和A[R]~A[RightEnd]归并成一个有序序列 */
int LeftEnd, NumElements, Tmp;
int i;
LeftEnd = R - 1; /* 左边终点位置 */
Tmp = L; /* 有序序列的起始位置 */
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd ) {
if ( A[L] <= A[R] )
TmpA[Tmp++] = A[L++]; /* 将左边元素复制到TmpA */
else
TmpA[Tmp++] = A[R++]; /* 将右边元素复制到TmpA */
}
while( L <= LeftEnd )
TmpA[Tmp++] = A[L++]; /* 直接复制左边剩下的 */
while( R <= RightEnd )
TmpA[Tmp++] = A[R++]; /* 直接复制右边剩下的 */
for( i = 0; i < NumElements; i++, RightEnd -- )
A[RightEnd] = TmpA[RightEnd]; /* 将有序的TmpA[]复制回A[] */
}
void MergeSort(int a[],int low,int high){
if(low<high){
if(low<high){
int mid = (low+high)/2;
MergeSort(a,low,mid);
MergeSort(a,mid+1,high);
int b[6];
Merge(a,b,low,mid,high);
}
}
}
int main(){
int a[6] = {
0,6,9,1,4,3};
Print(a,6);
MergeSort(a,0,6);
Print(a,6);
return 0;
}