各类排序算法

没有加什么模板之类的，全用的int型，下标有的从0开始有的从1开始

1.插入

#include <iostream>
#include <cstdio>
#define N 1005
using namespace std;
int n, a[N];
void InsertSort(int a[], int n) //下标从0开始
{
    int i, j, temp;
    for(i = 1; i < n; i++)
    {
        temp = a[i];
        for(j = i; j > 0 && temp < a[j - 1]; j--) a[j] = a[j - 1];
        a[j] = temp;
    }
}
int main()
{
    int i;
    scanf("%d", &n);
    for(i = 0; i < n; i++) scanf("%d", &a[i]);
    InsertSort(a, n);
    for(i = 0; i < n; i++) printf("%d\n", a[i]);
    return 0;
}

 

2.选择

 

 

#include <iostream>
using namespace std;
int a[105];
//下标从1开始
void SelectSort(int a[], int n)
{
    int i, j, pos;
    for(i = 1; i < n; i++)
    {
        pos = i;
        for(j = i; j <= n; j++)
        {
            if(a[j] < a[pos])
            pos = j;
        }
        int temp = a[pos];
        a[pos] = a[i];
        a[i] = temp;
    }
}
int main()
{
    int n, i;
    cin >> n;
    for(i = 1; i <= n; i++) cin >> a[i];
    SelectSort(a, n);
    for(i = 1; i <= n; i++)
    cout << a[i] << " ";
    cout << endl;
    return 0;
}

 

3.冒泡

 

#include <iostream>
using namespace std;
int a[105];
//下标从1开始
void BubbleSort(int a[], int n)
{
    int i, j;
    for(i = 1; i < n; i++)
    {
        for(j = 1; j <= n - i; j++)
        {
            if(a[j] > a[j + 1])
            {
                int temp = a[j + 1];
                a[j + 1] = a[j];
                a[j] = temp;
            }
        }
    }
}
int main()
{
    int n, i;
    cin >> n;
    for(i = 1; i <= n; i++)
        cin >> a[i];
    BubbleSort(a, n);
    for(i = 1; i <= n; i++)
    cout << a[i] << " ";
    cout << endl;
    return 0;
}

 

4.快排

 

#include <iostream>
using namespace std;
int n;
int a[105];
//下标从0开始
int partition(int a[], int low, int high)
{//快速排序中的一趟
    int key;//作为枢轴来使用
    key = a[low];
    while(low < high)
    {
        while(low < high && a[high] >= key)
        --high;
        a[low] = a[high];
        while(low < high && a[low] <= key)
        ++low;
        a[high] = a[low];
    }
    a[low] = key;
    return low;
}
void qsort(int a[], int low, int high)
{//快速排序的递归形式
    int loc;
    if(low < high)
    {
        loc = partition(a, low, high);//一趟排序结果的调用
        qsort(a, low, loc - 1);
        qsort(a, loc + 1, high);
    }
}
int main()
{
    int i;
    cin >> n;
    for(i = 0; i < n; i++) cin >> a[i];
    qsort(a, 0, n - 1);
    for(i = 0; i < n; i++) cout << a[i] << " ";
    cout << endl;
    return 0;
}

 

5.归并

 

#include <iostream>
#define N 105
using namespace std;
int n;
int a[N], t[N];
/* 归并 */
//下标从0开始
void Merge(int a[], int l, int m, int r)
{
    /* p指向输出区间 */
    int p = 0;
    /* i、j指向2个输入区间 */
    int i = l, j = m + 1;
    /* 2个输入区间都不为空时 */
    while(i <= m && j <= r)
    {/* 取关键字小的记录转移至输出区间 */
        if (a[i] > a[j])
            t[p++] = a[j++];
        else
            t[p++] = a[i++];
    }
    /* 将非空的输入区间转移至输出区间 */
    while(i <= m) t[p++] = a[i++];
    while(j <= r) t[p++] = a[j++];
    /* 归并完成后将结果复制到原输入数组 */
    for (i = 0; i < p; i++)
        a[l + i] = t[i];
}

/* 归并排序 */
void MergeSort(int a[], int l, int r)
{
    int m;
    if (l < r)
    {/* 将长度为n的输入序列分成两个长度为n/2的子序列 */
        m = (l + r) / 2;
        /* 对两个子序列分别进行归并排序 */
        MergeSort(a, l, m);
        MergeSort(a, m + 1, r);
        /* 将2个排好的子序列合并成最终有序序列 */
        Merge(a, l, m, r);
    }
}
int main()
{
    int i;
    cin >> n;
    for(i = 0; i < n; i++) cin >> a[i];
    MergeSort(a, 0, n - 1);
    for(i = 0; i < n; i++) cout << a[i] << " ";
    cout << endl;
    return 0;
}

 

6.堆排

 

#include <iostream>
using namespace std;
int n;
int a[105];
//下标从1开始
void HeapAdjust(int A[], int a, int z)
{
    int i, j;
    for(i = a, j = 2 * i; j <= z; i = j, j = 2 * i)
    { //i为父，j为子
        if(j < z && A[j + 1] > A[j]) j++;   //大顶堆，沿大孩子方向下行
        if(A[i] < A[j])
            swap(A[i], A[j]);
        else break;
    }
}
void HeapSort(int A[], int n)
{
    int i;
    for(i = n / 2; i >= 1; i--) //从倒数第一个非叶子结点，自下而上堆化
        HeapAdjust(A, i, n);
    for(i = n; i > 1; i--)
    { //交换A[1]与最后元素A[i]（i=n, ..., 1）, 再堆化
        swap(A[1], A[i]);
        HeapAdjust(A, 1, i - 1);
    }
}
int main()
{
    int i;
    cin >> n;
    for(i = 1; i <= n; i++)
    cin >> a[i];
    HeapSort(a, n);
    for(i = 1; i <= n; i++) cout << a[i] << " ";
    cout << endl;
    return 0;
}