实验 4

第二题

using namespace std;
class Graph {
	public:
		Graph(char t, int n);   
		void draw(); 	 
	private:
		char ch;
		int number;
};
Graph::Graph(char t, int n): ch(t), number(n) {}
void Graph::draw() 
{
	int i,j;
	for(i=0;i<=number;i++)
	{
	for(j=0;j<=number-i;j++)
	cout<<" ";	
	for(int j=0;j<2*i-1;j++)
            cout<<number;
        cout<<endl;
}
}
int main() {
	Graph graph1('*',5), graph2('$',7) ; 
	graph1.draw();
	graph2.draw(); 
	
	return 0; 
} ```
第三题

include

using namespace std;
class Fraction
{
public:
Fraction():top(0),bottom(1) {};
Fraction(int a,int b):top(a),bottom(b) {};
Fraction(int c):top(c),bottom(1){};
void add(Fraction p);
void sub(Fraction p);
void mul(Fraction p);
void div(Fraction p);
void display()
{
cout<<top<<"/"<<bottom<<endl;
};
void op();
private:
int top;
int bottom;
};
void Fraction:: add(Fraction p)
{