23.冒泡排序

#include<iostream>

using namespace std;

int main()

{

    int arr[] = { 1,3,4,5,3,3,5,22,4,5,6,7 };

    int len = sizeof(arr) / sizeof(arr[0]);

    //冒泡排序1：先把最值放在最后面

    for (int i = 0; i < len-1; i++)

    {

        for (int j = 0; j < len - i - 1; j++)

        {

            if (arr[j] > arr[j + 1])

            {

                int a = arr[j];

                arr[j] = arr[j + 1];

                arr[j + 1] = a;

            }

        }

    }

    for (int i = 0; i < len; i++)

    {

        cout << arr[i] << endl;

    }

//冒泡排序2：先把最值换到最前面

    int arr1[5] = { 300,350,200,400,250 };

    //cout << sizeof(arr1) / sizeof(arr1[0]) - 1 << endl;

    for (int i = 0; i < sizeof(arr1) / sizeof(arr1[0]) - 1; i++)

    {

        for (int j = i + 1; j < sizeof(arr1) / sizeof(arr1[0]); j++)

        {

            if (arr1[i] > arr1[j])//后面的每个值与前面的某个值比较

            {

                int a = arr1[i];

                arr1[i] = arr1[j];

                arr1[j] = a;

            }

        }

    }

    for (int i = 0; i < sizeof(arr1) / sizeof(arr1[0]); i++)

    {

        cout << arr1[i] << endl;

    }

    //冒泡排序3：先把最值换到最前面，从后往前比较

    cout << "从后往前比较" << endl;

    int arr2[5] = { 300,350,200,400,250 };

    //cout << sizeof(arr2) / sizeof(arr2[0]) - 1 << endl;

    for (int i = 0; i < sizeof(arr2) / sizeof(arr2[0]) - 1; i++)

    {

        for (int j = sizeof(arr2) / sizeof(arr2[0])-2; j >=i; j--)//从后往前比较

        {

            if (arr2[j] > arr2[j+1])

            {

                int a = arr2[j];

                arr2[j] = arr2[j+1];

                arr2[j+1] = a;

            }

        }

    }

    for (int i = 0; i < sizeof(arr2) / sizeof(arr2[0]); i++)

    {

        cout << arr2[i] << endl;

    }

    system("pause");

    return 0;

}