1.封装一个类，实现对一个数求累和阶乘质数
#include <iostream>using namespace std;
int mproduct(int a){if(a>1){return a*mproduct((a-1));}else{return 1;}
}
class number{int a;
public:number():a(5){};number(int a):a(a){}void set(int a){this->a=a;}void sum(){int sun=0;for(int i=1;i<=a;i++){sun+=i;}cout<<"sun="<<sun<<endl;}void product(){cout<<mproduct(a)<<endl;}void primeNumber(){for(int j=1;j<a;j++){if(a%j==0){continue;}else{cout<<j<<" ";}}cout<<endl;}
};int main()
{number num;num.set(12);num.sum();num.product();num.primeNumber();return 0;
}
2.封装两个类，实现字符串交错输出
#include <iostream>using namespace std;
class A{string str;int a;
public:A():str("abcdefghijklmnopqrstuvwxyz"),a(0){}void mygetchar(){cout <<str.at(a)<<" ";a=(a+1)%26;}
};
class B{string str;int a;
public:B():str("1234567890"),a(0){}void mygetchar(){cout<<str.at(a)<<" ";a=(a+1)%10;}
};int main()
{A a;B b;int i=0;int len;cin>>len;while(i++<len){a.mygetchar();b.mygetchar();}return 0;
} 
3. 输入字符串，将字母和数字分别存入两个不同的类的对象，然后输出。
#include <iostream>
#include<cstring>
#include<stdio.h>
using namespace std;
class A{string a;public:A(){}void myinsert(char c){a+=c;}void show(){cout<<a<<endl;}
};
class B{string b;public:B(){}void myinsert(char c){b+=c;}void show(){cout<<b<<endl;}
public:};int main()
{string str;A A;B B;//char a[128];cin>>str;cout<<"字符串输入成功"<<endl;for(unsigned int i=0;i<str.length();i++){if(str.at(i)<'9'&&str.at(i)>'0'){A.myinsert(str.at(i));}else{B.myinsert(str.at(i));}}A.show();B.show();return 0;
}
