设计模式

单例

#include <iostream>
#include <string>
#include <memory>
#include <mutex>
#include <thread>using namespace std;class SingleTon{
protected://外部不可直接操作SingleTon(const string& value):_value(value) {cout<< "SingleTon Construct" <<endl;}~SingleTon() {cout<< "SingleTon Destruct" <<endl;}//静态成员   全局访问  智能指针   自动释放static  shared_ptr<SingleTon> singleton;string _value;public://禁止外部移动和拷贝SingleTon(const SingleTon && obj) = delete;void operator=(const SingleTon  obj) = delete;//提供静态接口  类名调用static shared_ptr<SingleTon> getInstance(const string& value){//call once 调用static once_flag s_flag;call_once(s_flag , [&](){ singleton = shared_ptr<SingleTon>(new SingleTon(value), [](SingleTon * singleton){ delete singleton;});});return singleton;}string pinrtValue(){return _value;}
};//变量重置
shared_ptr<SingleTon> SingleTon::singleton = nullptr;void printValue(const string & value){cout<< SingleTon::getInstance(value)->pinrtValue()<<endl;
}int main(){thread th1(printValue,"aaa");thread th2(printValue,"bbb");th1.join();th2.join();return 0;
}

排序算法

查找算法

二分查找

#include <iostream>
#include <vector>using namespace std;using Rank = int;class Fib{
private:Rank g ,f;public:Fib(Rank n){f =0; g= 1;  //f 代表 fib(k -1)  g 代表 fib(k)while(0 < n--){g = g + f;f = g - f;}}Rank get(){return g;}Rank next(){g = g + f;f = g -f;return g;};Rank pre(){f = g-f;g = g-f;return g;}
};template < typename T>
static Rank fibSearch(T *A,const T &e,Rank lo,Rank hi){for(Fib fib(hi - lo) ; lo < hi;){while( hi -lo < fib.get()) fib.pre();Rank mi = lo + fib.get() -1;(e < A[mi]) ? hi = mi : lo = mi + 1;}return lo - 1;
}int main(){std::vector<Rank> test{1,3,6,8,9,11,13,17,20} ;Rank index = fibSearch<Rank>(test.data(),14,0,test.size());cout << "index: " << index <<endl;return 0;
}