欢迎大家踊跃发贴啊！～～～～～～第一个程序
#include <iostream>
#include <iomanip>
#include <fstream>
#include <time.h>
#include <stdlib.h>
using namespace std;
int math1();
int math2();
int count1=0;
int x;
int y;
int w; 
int temp;
int n;
int z,i; 
int math1()
{ 
  srand(time(NULL));
for(i=1;i<=10;i++)
{
x=rand()%100;
y=1+rand()%100;
w=1+rand()%2;
  if(x<y)
  {
   temp=x;
   x=y;
      y=temp;
  }
  switch(w)
  {
   case 1:
    z=x+y;
    cout<<i<<"   "<<x<<" + "<<y<<" = ?"<<endl; 
    break;
   case 2:
    z=x-y;
    cout<<i<<"   "<<x<<" - "<<y<<" = ?"<<endl; 
    break;

}
cout<<"输入结果"<<endl;
cin>>n;
  if(n==z) 
  {  
    x=rand()%100;  
       y=1+rand()%100;
    w=1+rand()%2;
     if(x<y)   
{
   temp=x;
      x=y;
         y=temp;
   }
cout<<"Right,恭喜你"<<endl;
count1++;
}
else
{
ofstream oufile("d:\\ error.txt",ios::out);
cout<<"Error,再想想"<<endl;
cout<<"再做一遍"<<endl;
cin>>n;
if(n==z)
cout<<"Right,恭喜你"<<endl;
else
cout<<"正确答案"<<"  "<<z<<endl;
}}
cout<<"练习结束"<<"    "<<"做对题目数"<<count1<<endl;
return 0;
}

int math2()
{
srand(time(NULL));
for(i=1;i<=20;i++)
{
x=rand()%100;
y=1+rand()%100;
w=1+rand()%2;
  if(x<y)
  {
   temp=x;
   x=y;
      y=temp;
  }
  switch(w)
  {
   case 1:
    z=x+y;
    cout<<i<<"   "<<x<<" + "<<y<<" = ?"<<endl; 
    break;
   case 2:
    z=x-y;
    cout<<i<<"   "<<x<<" - "<<y<<" = ?"<<endl; 
    break;

}
cout<<"输入结果"<<endl;
cin>>n;
  if(n==z) 
  {  
    x=rand()%100;  
       y=1+rand()%100;
    w=1+rand()%2;
     if(x<y)   
{
   temp=x;
      x=y;
         y=temp;
   }
cout<<"Right,恭喜你"<<endl;
count1++;
}
else
{
cout<<"Error,再想想"<<endl;
cout<<"再做一遍"<<endl;
cin>>n;
if(n==z)
cout<<"Right,恭喜你"<<endl;
else
cout<<"正确答案"<<"  "<<z<<endl;
}}
cout<<"练习结束"<<"    "<<"做对题目数"<<count1<<endl;
return 0;
}

int main()
{

cout<<setw(45)<<"小学生算术练习"<<endl;
      cout<<"请选择练习题量"<<"   "<<"1.10题"<<"   "<<"2.20题"<<endl;
        cout<<"选1或者选2"<<endl;
   char m;
  cin>>m;
if(m='1')
math1();
else(m='2');
math2();
return 0;
}