各类排序C++实现
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
1 #include <iostream> 2 #include <cstdio> 3 #define N 1005 4 using namespace std; 5 int n, a[N]; 6 void InsertSort(int a[], int n) //下标从0开始 7 { 8 int i, j, temp; 9 for(i = 1; i < n; i++) 10 { 11 temp = a[i]; 12 for(j = i; j > 0 && temp < a[j - 1]; j--) a[j] = a[j - 1]; 13 a[j] = temp; 14 } 15 } 16 int main() 17 { 18 int i; 19 scanf("%d", &n); 20 for(i = 0; i < n; i++) scanf("%d", &a[i]); 21 InsertSort(a, n); 22 for(i = 0; i < n; i++) printf("%d\n", a[i]); 23 return 0; 24 }
2.选择
1 #include <iostream> 2 using namespace std; 3 int a[105]; 4 //下标从1开始 5 void SelectSort(int a[], int n) 6 { 7 int i, j, pos; 8 for(i = 1; i < n; i++) 9 { 10 pos = i; 11 for(j = i; j <= n; j++) 12 { 13 if(a[j] < a[pos]) 14 pos = j; 15 } 16 int temp = a[pos]; 17 a[pos] = a[i]; 18 a[i] = temp; 19 } 20 } 21 int main() 22 { 23 int n, i; 24 cin >> n; 25 for(i = 1; i <= n; i++) cin >> a[i]; 26 SelectSort(a, n); 27 for(i = 1; i <= n; i++) 28 cout << a[i] << " "; 29 cout << endl; 30 return 0; 31 }
3.冒泡
1 #include <iostream> 2 using namespace std; 3 int a[105]; 4 //下标从1开始 5 void BubbleSort(int a[], int n) 6 { 7 int i, j; 8 for(i = 1; i < n; i++) 9 { 10 for(j = 1; j <= n - i; j++) 11 { 12 if(a[j] > a[j + 1]) 13 { 14 int temp = a[j + 1]; 15 a[j + 1] = a[j]; 16 a[j] = temp; 17 } 18 } 19 } 20 } 21 int main() 22 { 23 int n, i; 24 cin >> n; 25 for(i = 1; i <= n; i++) 26 cin >> a[i]; 27 BubbleSort(a, n); 28 for(i = 1; i <= n; i++) 29 cout << a[i] << " "; 30 cout << endl; 31 return 0; 32 }
4.快排
1 #include <iostream> 2 using namespace std; 3 int n; 4 int a[105]; 5 //下标从0开始 6 int partition(int a[], int low, int high) 7 {//快速排序中的一趟 8 int key;//作为枢轴来使用 9 key = a[low]; 10 while(low < high) 11 { 12 while(low < high && a[high] >= key) 13 --high; 14 a[low] = a[high]; 15 while(low < high && a[low] <= key) 16 ++low; 17 a[high] = a[low]; 18 } 19 a[low] = key; 20 return low; 21 } 22 void qsort(int a[], int low, int high) 23 {//快速排序的递归形式 24 int loc; 25 if(low < high) 26 { 27 loc = partition(a, low, high);//一趟排序结果的调用 28 qsort(a, low, loc - 1); 29 qsort(a, loc + 1, high); 30 } 31 } 32 int main() 33 { 34 int i; 35 cin >> n; 36 for(i = 0; i < n; i++) cin >> a[i]; 37 qsort(a, 0, n - 1); 38 for(i = 0; i < n; i++) cout << a[i] << " "; 39 cout << endl; 40 return 0; 41 }
5.归并
1 #include <iostream> 2 #define N 105 3 using namespace std; 4 int n; 5 int a[N], t[N]; 6 /* 归并 */ 7 //下标从0开始 8 void Merge(int a[], int l, int m, int r) 9 { 10 /* p指向输出区间 */ 11 int p = 0; 12 /* i、j指向2个输入区间 */ 13 int i = l, j = m + 1; 14 /* 2个输入区间都不为空时 */ 15 while(i <= m && j <= r) 16 {/* 取关键字小的记录转移至输出区间 */ 17 if (a[i] > a[j]) 18 t[p++] = a[j++]; 19 else 20 t[p++] = a[i++]; 21 } 22 /* 将非空的输入区间转移至输出区间 */ 23 while(i <= m) t[p++] = a[i++]; 24 while(j <= r) t[p++] = a[j++]; 25 /* 归并完成后将结果复制到原输入数组 */ 26 for (i = 0; i < p; i++) 27 a[l + i] = t[i]; 28 } 29 30 /* 归并排序 */ 31 void MergeSort(int a[], int l, int r) 32 { 33 int m; 34 if (l < r) 35 {/* 将长度为n的输入序列分成两个长度为n/2的子序列 */ 36 m = (l + r) / 2; 37 /* 对两个子序列分别进行归并排序 */ 38 MergeSort(a, l, m); 39 MergeSort(a, m + 1, r); 40 /* 将2个排好的子序列合并成最终有序序列 */ 41 Merge(a, l, m, r); 42 } 43 } 44 int main() 45 { 46 int i; 47 cin >> n; 48 for(i = 0; i < n; i++) cin >> a[i]; 49 MergeSort(a, 0, n - 1); 50 for(i = 0; i < n; i++) cout << a[i] << " "; 51 cout << endl; 52 return 0; 53 }
6.堆排
1 #include <iostream> 2 using namespace std; 3 int n; 4 int a[105]; 5 //下标从1开始 6 void HeapAdjust(int A[], int a, int z) 7 { 8 int i, j; 9 for(i = a, j = 2 * i; j <= z; i = j, j = 2 * i) 10 { //i为父，j为子 11 if(j < z && A[j + 1] > A[j]) j++; //大顶堆，沿大孩子方向下行 12 if(A[i] < A[j]) 13 swap(A[i], A[j]); 14 else break; 15 } 16 } 17 void HeapSort(int A[], int n) 18 { 19 int i; 20 for(i = n / 2; i >= 1; i--) //从倒数第一个非叶子结点，自下而上堆化 21 HeapAdjust(A, i, n); 22 for(i = n; i > 1; i--) 23 { //交换A[1]与最后元素A[i]（i=n, ..., 1）, 再堆化 24 swap(A[1], A[i]); 25 HeapAdjust(A, 1, i - 1); 26 } 27 } 28 int main() 29 { 30 int i; 31 cin >> n; 32 for(i = 1; i <= n; i++) 33 cin >> a[i]; 34 HeapSort(a, n); 35 for(i = 1; i <= n; i++) cout << a[i] << " "; 36 cout << endl; 37 return 0; 38 }
