排序算法

冒泡排序

從左向右掃描數據，選著最大的數據。

要點：比較相鄰的兩個數，如果左邊的數大于右邊的數就進行交換。

template<class T>

void BubbleSort(T *array, const int length)

{

???????? for (int i = 0; i <length-1; i++)

???????? {

?????????????????? for (int j = i+1; j <length; j++)

?????????????????? {

??????????????????????????? if (array[i]> array[j])

???????????????????????????????????? std::swap(array[i], array[j]);

?????????????????? }

???????? }

}

選擇排序

從當前未排序的整數中選著一個最小的整數，將他放在已排序按的整數列表的最后。

要點：選擇排序最小的

冒泡排序與選擇排序

template<class T>

void SelectSort(T *array, const int length)

{

???????? for (int i = 0; i < length; i++)

???????? {

?????????????????? int min = i;

?????????????????? for (int j = i + 1; j < length; j++)

?????????????????? {

??????????????????????????? if (array[j] < array[min])

???????????????????????????????????? min = j;

?????????????????? }

?????????????????? std::swap(array[i], array[min]);

???????? }

}

?

?

?

查找算法

順序查找

數據沒排序，查找速度慢

template<class T>

int SequentSearch(T *array, const int length,const T x)

{

???????? int i;

???????? for (i = 0; i < length; i++)

???????? {

?????????????????? if (array[i] == x)

??????????????????????????? return i;

???????? }

???????? return -1;

}

二分查找

數據需要排序，查找速度快

template<class T>

int BinarySearch(T *array, const int length, const T x)

{

???????? int low, hight, mid;

???????? low = 0, hight = length - 1;

?

???????? while (low <= hight)

???????? {

?????????????????? mid = (low + hight) / 2;

?????????????????? if (array[mid] == x)

??????????????????????????? return mid;

?????????????????? else if (array[mid] < x)

??????????????????????????? low = mid + 1;

?????????????????? else if (array[mid] >x)

??????????????????????????? hight = mid - 1;

???????? }

???????? return -1;

}

?

?

?

?

遞歸算法

難點：多入口遞歸算法的實現，遞歸實現的代碼都可以是使用使用循來實現，遞歸耗費內存，在自己調用自己是，是否應該加return，需要考慮，一般需要加上return。遞歸算法需要深入研究才能掌握。

遞歸二分查找算法

template<class T>

int Recursive_BinarySearch(T * array, const int length, const T x,const int left ,const int right)

{

???????? if (left <= right)

???????? {

?????????????????? int mid = (left + right) / 2;

?????????????????? if (x < array[mid])

??????????????????????????? return Recursive_BinarySearch(array, length, x, left, mid - 1);

? ? ? ? ? ? ? ? ? ? ? ? ? ?// 注意函數前需要加一個return，沒加return，結果不正確

?????????????????? else if(x > array[mid])

??????????????????????????? return Recursive_BinarySearch(array, length, x, mid+ 1, right);

?????????????????? else return mid;

???????? }

???????? return-1;

}

?

遞歸實現排列組合問題

template<class T>

void Permutations(T * array,int left,int right)

{

???????? if (left == right)

???????? {

?????????????????? for (int i = 0; i < right; i++)

??????????????????????????? cout << array[i];

?????????????????? cout << endl;

???????? }

???????? else

???????? {

?????????????????? for (int i = left; i < right; i++)

?????????????????? {

??????????????????????????? std::swap(array[left], array[i]);

??????????????????????????? Permutations(array,left+1,right);

??????????????????????????? std::swap(array[left], array[i]);

?????????????????? }

???????? }

}

#include<iostream> using namespace std;//排序算法 template<class T> void BubbleSort(T *array, const int length);//冒泡 template<class T> void B_sort(T *array, const int length); template<class T> void SelectSort(T *array, const int length);//選擇//T *array,使用指針,速度快，傳遞的數數組的地址，T array[],這種寫法為傳值，需要大量復制數據//查找算法 template<class T> int SequentSearch(T *array, const int length, const T x);//順序查找，沒排序的數據 template<class T>int Recursive_BinarySearch(T *array, const int length, const T x,const int left=0,const int right=0);//遞歸二分查找，排序的數據 template<class T>int BinarySearch(T *array, const int length, const T x);//二分查找，排序的數據 template<class T>void Permutations(T *array,int left,int right);//實現數組中元素的所有組合 int main() {double a[] = { 1.1,1.9,2.5,9.2,9.5,4.0,3.2,4.5,6.7,8.4 };BubbleSort(a, 10); cout << "冒泡排序：" << endl;for (int i = 0; i < 10; i++){cout << a[i] << endl;}B_sort(a, 10); cout << "冒泡排序：" << endl;for (int i = 0; i < 10; i++){cout << a[i] << endl;}int b[] = {5,6,1,4,8,3,6,7,2,9,0 };SelectSort(b, 10); cout << "選擇排序：" << endl;for (int i = 0; i < 10; i++){cout << b[i] << endl;}double x = 4.0;int i = SequentSearch(a, 10, x);if (i > 0){cout << "順序查找：" << endl; cout << i<<","<<a[i] << endl;}int y =8;int j = BinarySearch(b, 10,y);if (j> 0)cout << j<< "," << b[j] << endl;double z =5;int k = Recursive_BinarySearch(a, 10,z,0,10);if (k > 0){cout << "遞歸查找：" << endl;cout << k << "," << b[k] << endl;}char ch[] = { 'a','b','c' };cout << "字母組合：" << endl;Permutations(ch,0, 3);system("pause");return 0; }template<class T> void BubbleSort(T *array, const int length) {for (int i = 0; i < length; i++){for (int j = 0; j < length - 1 - i; j++){if(array[j]> array[j+1])std::swap(array[j],array[j+1]);}} }template<class T> void B_sort(T *array, const int length) {for (int i = 0; i <length-1; i++){for (int j = i+1; j <length; j++){if (array[i]> array[j])std::swap(array[i], array[j]);}} }template<class T> void SelectSort(T *array, const int length) {for (int i = 0; i < length; i++){int min = i;for (int j = i + 1; j < length; j++){if (array[j] < array[min])min = j;}std::swap(array[i], array[min]);} }template<class T> int SequentSearch(T *array, const int length,const T x) {int i;for (i = 0; i < length; i++){if (array[i] == x)return i;}return -1; }template<class T> int Recursive_BinarySearch(T * array, const int length, const T x,const int left ,const int right) {if (left <= right){int mid = (left + right) / 2;if (x < array[mid])return Recursive_BinarySearch(array, length, x, left, mid - 1);// 注意函數前需要加一個return，沒加return，結果不正確else if(x > array[mid])return Recursive_BinarySearch(array, length, x, mid+ 1, right);else return mid;}return-1; }template<class T> int BinarySearch(T *array, const int length, const T x) {int low, hight, mid;low = 0, hight = length - 1;while (low <= hight){mid = (low + hight) / 2;if (array[mid] == x)return mid;else if (array[mid] < x)low = mid + 1;else if (array[mid] >x)hight = mid - 1;}return -1; }template<class T> void Permutations(T * array,int left,int right) {if (left == right){for (int i = 0; i < right; i++)cout << array[i];cout << endl;}else{for (int i = left; i < right; i++){std::swap(array[left], array[i]);Permutations(array,left+1,right);std::swap(array[left], array[i]);}} }

結果：

?

?

?

?

?

?

?

?

?

總結

以上是生活随笔為你收集整理的排序算法-查找算法的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。