常见的几种排序算法

  1 #include <stdio.h>
  2 
  3 //直接插入排序算法
  4 void InsertSort(int a[], int size)
  5 {
  6 int i, j;
  7 int key; //待插入的值
  8 for (j = 1; j < size; j++)
  9 {
 10 key = a[j];
 11 i = j - 1;
 12 while (i >= 0 && a[i]>key)
 13 {
 14 a[i + 1] = a[i];
 15 i--;
 16 }
 17 a[i + 1] = key;
 18 }
 19 }
 20 
 21 /*
 22 Shell排序算法:
 23 1)设置步长d=n/2；
 24 2)分组进行直接插入排序
 25 3)改变步长d=d/2，重复2）和3），直到d<=0;
 26 */
 27 void ShellSort(int a[], int size)
 28 {
 29 int i, j, key;
 30 int d = size / 2;    //步长
 31 
 32 while (d > 0)
 33 {
 34 for (j = d; j < size; j++)
 35 {
 36 i = j - d;
 37 key = a[j];
 38 while (i >= 0 && a[i] > key)
 39 {
 40 a[i + d] = a[i];
 41 i = i - d;
 42 }
 43 a[i + d] = key;
 44 }
 45 d = d / 2;
 46 }
 47 }
 48 
 49 //冒泡排序
 50 void BubbleSort(int a[], int size)
 51 {
 52 int i, j, temp;
 53 for (i = 0; i < size; i++)
 54 {
 55 for (j = size-1;j>i;j--)
 56 {
 57 if (a[j] < a[j - 1])
 58 {
 59 temp = a[j];
 60 a[j] = a[j - 1];
 61 a[j - 1] = temp;
 62 }
 63 }
 64 }
 65 }
 66 
 67 //快速排序
 68 void QuickSort(int a[], int low, int high)
 69 {
 70 int temp_low = low;
 71 int temp_high = high;
 72 int i;
 73 if (low < high)
 74 {
 75 int key,temp;
 76 bool flag = true;
 77 key = a[low];
 78 while (low<high)
 79 {
 80 if (flag)
 81 {
 82 if (a[high]<key)
 83 {
 84 temp = a[high];
 85 a[high] = a[low];
 86 a[low] = temp;
 87 low++;
 88 flag = false;
 89 }
 90 else
 91 {
 92 high--;
 93 }
 94 }
 95 else
 96 {
 97 if (a[low]>key)
 98 {
 99 temp = a[high];
100 a[high] = a[low];
101 a[low] = temp;
102 high--;
103 flag = true;
104 }
105 else
106 {
107 low++;
108 }
109 }
110 
111 }
112 i = low;
113 a[i] = key;
114 QuickSort(a, temp_low, i - 1);
115 QuickSort(a, i + 1, temp_high);
116 }
117 }
118 
119 //直接选择排序
120 void SelectSort(int a[], int size)
121 {
122 int i, j;
123 int k; //存放最小值的下标
124 int temp;
125 for (i = 0; i < size; i++)
126 {
127 k = i;
128 for (j = i+1; j < size; j++)
129 {
130 if (a[j] < a[k])
131 k = j;
132 }
133 temp = a[i];
134 a[i] = a[k];
135 a[k] = temp;
136 }
137 }
138 
139 void main()
140 {
141 int a[10] = { 5, 4, 2, 5, 7, 9, 8, 1, 6, 0 };
142 int i;
143 
144 //InsertSort(a, 10);
145 //ShellSort(a, 10);
146 //BubbleSort(a, 10);
147 //QuickSort(a, 0, 9);
148 SelectSort(a, 10);
149 for (i = 0; i < 10; i++)
150 {
151 printf("%d ", a[i]);
152 }
153 
154 printf("\n");
155 }