// 例1#include <iostream>#include <cstdlib>using namespace std;void main(){    int c = 0, a = 0, b = 0;    cout<<"两次次使用 ++a"<<endl;    c =  (++a) + (++a);     cout<<"the value of c is "<<c<<endl;    c = a + a;    cout<<"the value of c is "<<c<<endl<<endl;        cout<<"两次次使用 b++"<<endl;    c = (b++) + (b++);    cout<<"the value of c is "<<c<<endl;    c = b + b;    cout<<"the value of c is "<<c<<endl<<endl;    a = 0;//先重新初始化下 变量a    cout<<"a++ 与 ++a 的混合使用, a++在前"<<endl;    c =  (++a) + (a++);     cout<<"the value of c is "<<c<<endl;    c = a + a;    cout<<"the value of c is "<<c<<endl<<endl;    a = 0;//先重新初始化下 变量a    cout<<"a++ 与 ++a 的混合使用, a++在后"<<endl;    c = (a++) + (++a);     cout<<"the value of c is "<<c<<endl;    c = a + a;    cout<<"the value of c is "<<c<<endl<<endl;    a = 0;//先重新初始化下 变量a    cout<<"一个 a++ 与 两个 ++a 的混合使用"<<endl;    c = (a++) +(++a) + (++a);     cout<<"the value of c is "<<c<<endl;    c = a + a + a;    cout<<"the value of c is "<<c<<endl<<endl;    a = 0;//先重新初始化下 变量a    cout<<"两个 a++ 与 一个 ++a 的混合使用"<<endl;    c = (a++) + (a++) + (++a);     cout<<"the value of c is "<<c<<endl;    c = a + a + a;    cout<<"the value of c is "<<c<<endl<<endl;    system("pause");}