#include <iostream>
using namespace std;
int main()
{cout<<"Hello, World\n";return 0;
}

#include <iostream>
using namespace std;
int main( )
{cout<<"Enter two numbers: "<<endl;int v1, v2;cin>>v1>>v2;cout<<"The product of"<<v1<<" and "<<v2<<" is "<<v1 * v2<<endl;system("PAUSE");return 0;
}

#include <iostream>
using namespace std;
int main( )
{cout<<"Enter two numbers: "<<endl;int v1, v2;cin>>v1>>v2;cout<<"The sum of";cout<<v1;cout<<" and ";cout<<v2;cout<<" is ";cout<<v1 + v2;cout<<endl;system("PAUSE");return 0;
}

#include <iostream>
using namespace std;
int main( )
{int i, sum=0;for(i=50; i<=100; ++i)sum+=i;cout<<"sum of 50 to 100 is "<<sum<<endl;system("PAUSE");return 0;
}

#include <iostream>
using namespace std;
int main( )
{int i, sum;i=50;sum=0;while(i++<=100)sum+=i;cout<<"sum of 50 to 100 is "<<sum<<endl;system("PAUSE");return

#include <iostream>
using namespace std;
int main( )
{int i=10;while(i>=0)cout<<i--<<endl;return 0;
}

#include <iostream>
using namespace std;
int main( )
{for(int i=10; i >=0; --i)cout<<i<<endl;　　return 0;
}

#include <iostream>
using namespace std;
int main( )
{int a, b;cout<<"请输入两个数： ";cin>>a>>b;cout<<"较大的一个数是: "<< ((a >= b)? a : b)<<endl;system("PAUSE");return 0;
}

#include <iostream>
using namespace std;
int main( )
{int num, a;num=0;while(cin>>a) if(a < 0) num++;cout<<"输入的负数数量为: "<<num<<endl;　　return 0;
}

#include <iostream>
using namespace std;
void print(int a, int b)
{a++;while(a < b)cout<<a++<<" ";cout<<endl;
}
int main( )
{int a,b,i;cout<<"请输入两个数： ";cin>>a>>b;if(a < b)print(a,b);elseprint(b,a);　　return 0;
}

#include <iostream>
#include "Sales_item.h"
using namespace std;
int main( )
{Sales_item book;cout<<"输入交易:"<<endl;while(cin>>book) {cout<<"售出书的本数、总收入、平均价格："<<endl;cout<<book<<endl;}system("PAUSE");return 0;
}

#ifndef SALESITEM_H
#define SALESITEM_H// Definition of Sales_item class and related functions goes here
#include <iostream>
#include <string>class Sales_item {
friend bool operator==(const Sales_item&, const Sales_item&);
// other members as before
public:// added constructors to initialize from a string or an istreamSales_item(const std::string &book):isbn(book), units_sold(0), revenue(0.0) { }Sales_item(std::istream &is) { is >> *this; }friend std::istream& operator>>(std::istream&, Sales_item&);friend std::ostream& operator<<(std::ostream&, const Sales_item&);
public:// operations on Sales_item objects// member binary operator: left-hand operand bound to implicit this pointerSales_item& operator+=(const Sales_item&);// other members as beforepublic:// operations on Sales_item objectsdouble avg_price() const;bool same_isbn(const Sales_item &rhs) const{ return isbn == rhs.isbn; }// default constructor needed to initialize members of built-in typeSales_item(): units_sold(0), revenue(0.0) { }
// private members as before
private:std::string isbn;unsigned units_sold;double revenue;};// nonmember binary operator: must declare a parameter for each operand
Sales_item operator+(const Sales_item&, const Sales_item&);inline bool
operator==(const Sales_item &lhs, const Sales_item &rhs)
{// must be made a friend of Sales_itemreturn lhs.units_sold == rhs.units_sold &&lhs.revenue == rhs.revenue &&lhs.same_isbn(rhs);
}inline bool
operator!=(const Sales_item &lhs, const Sales_item &rhs)
{return !(lhs == rhs); // != defined in terms of operator==
}using std::istream; using std::ostream;// assumes that both objects refer to the same isbn
inline
Sales_item& Sales_item::operator+=(const Sales_item& rhs)
{units_sold += rhs.units_sold; revenue += rhs.revenue; return *this;
}// assumes that both objects refer to the same isbn
inline
Sales_item
operator+(const Sales_item& lhs, const Sales_item& rhs)
{Sales_item ret(lhs);  // copy lhs into a local object that we'll returnret += rhs;           // add in the contents of rhs return ret;           // return ret by value
}inline
istream&
operator>>(istream& in, Sales_item& s)
{double price;in >> s.isbn >> s.units_sold >> price;// check that the inputs succeededif (in)s.revenue = s.units_sold * price;else s = Sales_item();  // input failed: reset object to default statereturn in;
}inline
ostream&
operator<<(ostream& out, const Sales_item& s)
{out << s.isbn << "\t" << s.units_sold << "\t" << s.revenue << "\t" <<  s.avg_price();return out;
}inline
double Sales_item::avg_price() const
{if (units_sold) return revenue/units_sold; else return 0;
}
#endif

View Code

#include <iostream>
#include "Sales_item.h"
using namespace std;
int main( )
{Sales_item trans1, trans2;cout<<"读入交易："<<endl;cin>>trans1>>trans2;if(trans1.same_isbn(trans2))cout<<"两笔交易具有相同的ISBN，和为:"<<endl<<trans1 + trans2;elsecout<<"两笔交易没有相同的ISBN";return 0;
}

#include <iostream>
#include "Sales_item.h"
using namespace std;
int main( )
{Sales_item sum, trans;cout<<"读入交易："<<endl;if(cin>>sum) {while(cin>>trans) {if(sum.same_isbn(trans))sum += trans;else {cout<<"不同的ISBN！"<<endl;return -1;}}} else {cout<<"no data!"<<endl;return -1;}return 0;
}

#include <iostream>
#include <map>
#include <string>
#include "Sales_item.h"
using namespace std;
int main( )
{Sales_item trans;cout<<"读入交易："<<endl;cin>>trans;map<string, int> count;count[trans.getIsbn()]++;while(cin>>trans) {++count[trans.getIsbn()];}map<string, int>::iterator it;for(it=count.begin(); it!=count.end(); it++)cout<<it->first<<":"<<it->second<<endl;system("PAUSE");return 0;
}