重载的应用
#include<iostream>using namespace std;class Triangle{public:Triangle(int a,int b){height=a;base=b;}friend ostream& operator<<(ostream& output,Triangle& T);private:int height,base;};ostream& operator<<(ostream& output,Triangle& T){int i,j,h,k;i=j=T.base-1;for(h=T.height-1;h;h--){for(k=i;k;k--)output<<' ';output<<'*';if(j!=i){for(k=j-i-1;k;k--)output<<' ';output<<'*';}i--;output<<endl;}for(k=0;k<T.base;k++)output<<'*';output<<endl;return output;}int main(){Triangle t1(5,5),t2(10,10),t3(12,12);cout<<t1<<endl;cout<<t2<<endl;cout<<t3<<endl;system("pause");return 0;}