【C/C++学院】0829-位容器multimapmutisetString/算法函数兰不达表达式以及类重载/GPU编程

位容器multimapmutisetString

Multiset

#include <set>#include <iostream>using namespace std;void mainA(){multiset<int> myset;myset.insert(100);myset.insert(101);myset.insert(100);myset.insert(103);myset.insert(100);auto pfind = myset.find(101);std::cout << *pfind << std::endl;auto allfind = myset.equal_range(100);//找到红黑树的链表节点，遍历所有的元素//find链表的头结点，second最后一个空节点，遍历所有的元素for (auto it = allfind.first; it != allfind.second;it++){cout << *it << endl;}cin.get();}

Multimap

#include <iostream>#include <map>#include <string>using namespace std;void main2(){multimap<string, string> mymap;mymap.insert(pair<string, string>("yincheng", "a"));mymap.insert(pair<string, string>("yincheng1", "b"));mymap.insert(pair<string, string>("yincheng", "c"));mymap.insert(pair<string, string>("yincheng", "d"));auto ib = mymap.begin();auto ie = mymap.end();for (;ib!=ie;ib++){cout << (*ib).first << "   "<<(*ib).second << endl;}auto pfind = mymap.find("yincheng");cout << "\n\n\n";cout << (*pfind).first << "   " << (*pfind).second<< endl;cout << "\n\n\n";auto it = mymap.equal_range("yincheng");//从树节点吧关键字相同的链表全部拔下//first起点，，secondl链表最后的节点后面一个空节点，都是迭代器for (auto i = it.first; i != it.second;i++){cout << (*i).first << "   " << (*i).second << endl;}cin.get();cin.get();}

Bitset

#include <set>#include <bitset>#include <iostream>#include<string>using namespace std;void main3X(){//8 位， （215）代表构造的数据 bitset<8>bs(215);for (int i = 0; i < 8;i++)//最高位存储i=7上{cout << bs[i];}cin.get();cin.get();}void main3Y(){//8 位， （215）代表构造的数据 bitset<8>bs(215);for (int i = 7; i >=0; i--){cout << bs[i] << "  " << ~bs[i] << endl;}cin.get();cin.get();}void  main3Z(){float num = 1231231236.8;bitset<32> myset(num);for (int i = 31; i >=0;i--){cout << myset[i];}cin.get();}void  main3S(){int  num =-5;bitset<32> myset(num);for (int i = 31; i >= 0; i--){cout << myset[i];}string str = myset.to_string();cout <<"\n" <<str << endl;unsigned int data;data = myset.to_ulong();//补码cout << "\n" << data<< endl;cin.get();}void main345(){bitset<8>bs(255);bs.set(7, 0);//操作二进制位bs.set(0, 0);cout << bs.size() << endl;//位数//bs.reset();//全部清零//bs.none();//测试下是否有越位for (int i = 7; i >=0; i--)//最高位存储i=7上{cout << bs[i];}cin.get();}

String容器

#include<string>#include <iostream>#include <stdlib.h>using namespace std;//字符串初始化void main1s(){char str[124] = "china is  big";//str = "12321";C写法//string str1(str);//str1 = "china  is great";string str1("ABCDEFG");str1 = "china  is  china";std::cout << str1;cin.get();}void main2s(){string str1("ABCD");string str2("1234");string str3 = str1 + str2;std::cout << str3;char stra[12]="1231";char strb[24]="2132";//char strc[36] = stra + strb;cin.get();}void main3s(){string str1("ABCD");string str2("1234");str1.append(str2);str1 += str2;//字符串的增加std::cout << str1;cin.get();}void main4s(){string str1("ABCD");string str2("1234");//任意位置插入字符str1.insert(str1.begin(),'X');str1.insert(str1.end(), 'X');str1.insert(str1.begin()+3,3, 'X');std::cout << str1;cin.get();}void  main5s(){string str1("12345678");auto ib = str1.begin();auto ie = str1.end();for (;ib!=ie;ib++){cout << *ib << endl;}//str1.erase(str1.begin());//删除一个字符//str1.erase(str1.begin()+3,str1.end()-2);//删除某个字符串str1.erase(3, 4);//c从第三个字符开始删除四个字符cout << str1 << endl;cin.get();}void main6s(){string str1("12345678china");str1.replace(5, 3, "china");//从0到第三个字符替换为china//replace,1位置，长度，字符串cout << str1 << endl;cin.get();}void mainA1(){string str("233锄禾日当午,谭胜把地雷买下土,谭胜来跳舞，炸成250");//cout << (int)str.find("谭胜大爷") << endl;//int pos = str.find(",");//找到第一个皮配的，不匹配返回-1，//int pos = str.rfind("谭胜");//找到第一个皮配的，不匹配返回-1，//int pos = str.find("谭胜");cin.get();}void mainA2(){string str("ab123mn");//int pos = str.find_first_of("123");//find_firstof是第一个找到与字符串皮配字符位置//int pos = str.find_first_not_of("abc");//find_firstof是第一个找到与字符串不皮配字符位置//int pos = str.find_last_of("123");//find_firstof是最后一个找到与字符串皮配字符位置int pos = str.find_last_not_of("123");cout << pos << endl;cin.get();}void main1234(){string str1 = "calc";string str2 = "ABC1";char strA[5] = "Asd";char strB[5] = "Asd";cout <<( str1 == str2) << endl;//重载了运算符cout << (strA == strB) << endl;//比较地址cout << str1.empty()<<endl;////是否为空const char *p = str1.c_str();system(p);cin.get();}void main(){//谭胜 是 流氓string str("abc is abc  china is china");//int pos = str.find('a', 0);//字符也一样//std::cout << pos << endl;//pos = str.find('a', pos+1);//std::cout << pos << endl;int pos = str.find("abc", 0);//find从指定位置查找std::cout << pos << endl;    pos = str.find("abc", pos+3);std::cout << pos << endl;cin.get();}

算法函数兰不达表达式以及类重载

#include <iostream>#include <vector>#include <algorithm>#include <functional>using namespace std;template<class T>  //模板类，实现对于某些容器元素的操作class add{public:void operator()( T &t)//重载（）运算符，进行操作{t *= 2;std::cout << t<<"\n";}};void  go(int a){a *= 2;std::cout << a << "\n";}void main(){vector<int> myv;myv.push_back(10);myv.push_back(9);myv.push_back(7);myv.push_back(9);add<int> addA;//省略，//for_each(myv.begin(), myv.end(), addA);//for_each(myv.begin(), myv.end(), add<int>());//for_each(myv.begin(), myv.end(), go);auto fun = [](int a, int b){ return a + b; };//Lanmba表达式auto funA = [](int a){a *= 2; cout << a << endl; };cout << fun(1, 2) << endl;for_each(myv.begin(), myv.end(), funA);for_each(myv.begin(), myv.end(), [](int a){a *= 2; cout << a << endl; });cin.get();}

GPU编程

比特币挖矿，经常使用gpu进行计算。

Helloworld

//win7 无法对gpu进行直接的调试#include <amp.h>//gpu计算#include <iostream>using namespace concurrency;using namespace std;void main(){int a[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };array_view<int> av(10,a);//GPU计算结构，av存储到GPU显存，根据数组初始化  //=直接操作AV，（index<1>idx）操作每一个元素//extent每一个元素//restrict (amp) 定位GPU执行parallel_for_each(av.extent, [=](index<1>idx) restrict (amp) {av[idx] += 123; });for (int i = 0; i < 10;i++)    {std::cout << av[i] << endl;     }cin.get();}

Gpu调试，需要进行如下的设置

单点测试

#include <iostream>  #include <amp.h>#include <WinBase.h>//操作系统的底层文件，测试时间#define COUNT 100000float nickName_GPU[COUNT];float nickName_CPU[COUNT];double rungpu(int num) restrict(amp)//限定了只能在GPU内部执行{double temp = 0;for (int i = 0; i < num; i++){temp += i;}return temp;}double runcpu(int num) restrict(cpu) //只能在CPU内部执行{double temp = 0;for (int i = 0; i < num; i++){temp += i;}return temp;}double runcpugpu(int num) restrict(amp, cpu)//并发执行{double temp = 0;for (int i = 0; i < num; i++){temp += i;}return temp;}int main(){LARGE_INTEGER freq;LARGE_INTEGER strt;LARGE_INTEGER ed;//统计时间， 可以精确到毫秒QueryPerformanceFrequency(&freq);QueryPerformanceCounter(&strt);//查询时间double dx[1] = { 0.0 };//数据， 一个元素的数组double  db = 0.0;concurrency::array_view<double> myview(1, dx);//转到gpu进行计算parallel_for_each(myview.extent,[=](concurrency::index<1> idx) restrict(amp){myview[idx] += rungpu(20000000);});myview.synchronize();//显式等待GPU计算完成并将数据打回内存printf("%f\n", dx[0]);QueryPerformanceCounter(&ed);//把每一毫秒全到精确的显示出来printf("GPU耗时: %d 毫秒\r\n", (ed.QuadPart - strt.QuadPart) * 1000 / freq.QuadPart);QueryPerformanceCounter(&strt);printf("%f\n", runcpu(20000000));QueryPerformanceCounter(&ed);printf("CPU耗时: %d 毫秒\r\n", (ed.QuadPart - strt.QuadPart) * 1000 / freq.QuadPart);puts("测试结束");getchar();return 0;}int mainW(void)//测试并行计算{LARGE_INTEGER freq;LARGE_INTEGER strt;LARGE_INTEGER ed;QueryPerformanceFrequency(&freq);QueryPerformanceCounter(&strt);concurrency::array_view<float> myView(COUNT, nickName_GPU); //将数据打入显存  ，100000个元素的数组concurrency::parallel_for_each(myView.extent, [=](concurrency::index<1> idx) restrict(amp){for (int i = 0; i < COUNT/10; i++){myView[idx] = (myView[idx] + 0.1f) / 2.3f;}});myView.synchronize();//显式等待GPU计算完成并将数据打回内存  QueryPerformanceCounter(&ed);printf("GPU耗时: %d 毫秒\r\n", (ed.QuadPart - strt.QuadPart) * 1000 / freq.QuadPart);QueryPerformanceCounter(&strt);for (int idx = 0; idx < COUNT; idx++){for (int i = 0; i < COUNT/10; i++){nickName_CPU[idx] = (nickName_CPU[idx] + 0.1f) / 2.3f;}}QueryPerformanceCounter(&ed);printf("CPU耗时: %d 毫秒\r\n", (ed.QuadPart - strt.QuadPart) * 1000 / freq.QuadPart);for (int idx = 0; idx < COUNT; idx++){if (nickName_CPU[idx] != nickName_GPU[idx]){puts("CPU和GPU的计算结果不相符！");getchar();return 0;}}puts("测试结束");getchar();return 0;}

Cpu的频率快与gpu，适合于单点计算，但是gpu的容器比较多，适合并行计算。

Cpu优势在于单点计算。围绕一个计算器，只计算一个数，计算速度最快。

Gpu优势：并发计算。Gpu加速程序，