【整理】常見的排序算法

常見的排序算法

  1 #include<iostream>
  2 using namespace std;
  3 
  4 void quick(int a[],int left, int right)
  5 {
  6     if (left == right)
  7         return;
  8     int index = (right + left + 1) / 2;
  9     int temp;
 10     temp = a[index];
 11     a[index] = a[right];
 12     a[right] = temp;
 13     int p = 0;
 14     int prev = -1;
 15     while (p != right)
 16     {
 17         if (a[p] >= a[right])
 18         {
 19             if ((p - prev) != 1)
 20             {
 21                 prev++;
 22                 temp = a[p];
 23                 a[p] = a[prev];
 24                 a[prev] = temp;
 25             }
 26             else
 27                 prev++;
 28         }
 29         p++;
 30     }
 31     prev++;
 32     temp = a[p];
 33     a[p] = a[prev];
 34     a[prev] = temp;
 35     if(prev!=left)
 36         quick(a, left, prev-1);
 37     if(prev!=right)
 38         quick(a, prev+1, right);
 39 }
 40 
 41 int main()
 42 {
 43     int n,temp;
 44     cout << "請輸入數組個數：" << endl;
 45     cin >> n;
 46     int *a = new int [n];
 47     for (int i = 0; i < n; i++)
 48     {
 49         cin >> temp;
 50         a[i] = temp;
 51     }
 52     
 53     //冒泡排序-從小到大
 54     for(int i=0;i<n-1;i++)
 55         for(int j=0;j<n-1-i;j++)
 56             if (a[j] > a[j + 1])
 57             {
 58                 temp = a[j];
 59                 a[j] = a[j + 1];
 60                 a[j + 1] = temp;
 61             }
 62     for (int i = 0; i < n; i++)
 63         cout << a[i];
 64     cout << endl;
 65 
 66     //選擇排序-從大到小
 67     int i,j,max;
 68     for (i = 0; i < n - 1; i++)
 69     {
 70         max = i;
 71         for (j = i; j < n; j++)
 72             if (a[j] > a[max])
 73                 max = j;
 74         if (max != i)
 75         {
 76             temp = a[i];
 77             a[i] = a[max];
 78             a[max] = temp;
 79         }
 80     }
 81     for (int i = 0; i < n; i++)
 82         cout << a[i];
 83     cout << endl;
 84 
 85     //插入排序-從小到大
 86     for (i = 1; i < n; i++)
 87     {
 88         temp = a[i];
 89         j = i - 1;
 90         while (j >= 0 && a[j] > temp)
 91         {
 92             a[j + 1] = a[j];
 93             j--;
 94         }
 95         a[j + 1] = temp;
 96     }
 97     for (int i = 0; i < n; i++)
 98         cout << a[i];
 99     cout << endl;
100     
101     //快速排序-從大到小
102     quick(a,0, n - 1);
103     for (int i = 0; i < n; i++)
104         cout << a[i];
105     cout << endl;
106 
107     delete[] a;
108     system("pause");
109     return 0;
110 
111 }