7.5

#include <iostream>#include <fstream> using namespace std; struct staff  {int num;    char name[20];   int age;     double  pay; }; int main()  {   staff staf[7]={2001,"Li",34,1200,2002,"Wang",23,2222,2003,"Fun",33,3333,  3333,"Xue",45,4444,5555,"Ling",39,6666},staf1;     fstream iofile("staff.dat",ios::in|ios::out|ios::binary); if(!iofile)  {cerr<<"open error!"<<endl;    abort();   }  int i,m,num;    cout<<"Five staff :"<<endl; for(i=0;i<5;i++)    {cout<<staf[i].num<<" "<<staf[i].name<<" "<<staf[i].age<<" "<<staf[i].pay<<endl;   iofile.write((char *)&staf[i],sizeof(staf[i]));}  cout<<"please input data you want insert:"<<endl; for(i=0;i<2;i++)    {cin>>staf1.num>>staf1.name>>staf1.age>>staf1.pay;    iofile.seekp(0,ios::end);      iofile.write((char *)&staf1,sizeof(staf1));}  iofile.seekg(0,ios::beg);    for(i=0;i<7;i++)  {iofile.read((char *)&staf[i],sizeof(staf[i]));   cout<<staf[i].num<<" "<<staf[i].name<<" "<<staf[i].age<<" "<<staf[i].pay<<endl;    }   bool find;   cout<<"enter number you want search,enter 0 to stop.";  cin>>num;  while(num)  {find=false;     iofile.seekg(0,ios::beg); for(i=0;i<7;i++)    {iofile.read((char *)&staf[i],sizeof(staf[i]));  if(num==staf[i].num)     {  m=iofile.tellg();             cout<<num<<" is No."<<m/sizeof(staf1)<<endl;         cout<<staf[i].num<<" "<<staf[i].name<<" "<<staf[i].age<<" "<<staf[i].pay<<endl;          find=true;        break;        }   }    if(!find) cout<<"can't find "<<num<<endl;   cout<<"enter number you want search,enter 0 to stop."; cin>>num;  }   iofile.close(); return 0; }