超级图形计算器（供做数学题用）

#include<iostream>//超级图形计算器
#include<windows.h>
using namespace std;
const double PI=3.14159;
double s_changfangxing(double a,double b){
	return a*b;
}
double c_changfangxing(double a,double b){
	return a+a+b+b;
}
double c_zhengfangxing(double a){
	return a*4.0;
}
double c_sanjiaoxing(double a,double b,double c){
	return a+b+c;
}
double s_zhengfangxing(double a){
	return a*a;
}
double c_yuan(double r){
	return r*2.0*PI;
}
double s_yuan(double r){
	return r*r*PI;
}
double s_sanjiaoxing(double a,double h){
	return a*h/2.0;
}
double v_yuanzhu(double r,double h){
	return PI*r*r*h;
}
double s_yuanzhu(double r,double h){
	double d;
	d=r+r;
	return 2*PI*r*r+PI*d*h;
}
double v_yuanzhui(double r,double h){
	double a;
	a=PI*r*r*h;
	return a/3.0;
}
double v_changfangti(double a,double b,double c){
	return a*b*c;
}
double v_zhengfangti(double a){
	return a*a*a;
}
double sb_changfangti(double a,double b,double c){
	return 2.0*(a*b+a*c+b*c);
}
double sb_zhengfangti(double a){
	return 6.0*a*a;
}
double sb_yuanzhu(double r,double h){
	return 2*s_yuan(r)+c_yuan(r)*h;
}
int main()
{
  int a,b,c,d,e;
  bool flag=true;
  double c_chang_a,c_chang_b,c_zheng_a,c_yuan_r,c_sanjiaoxing_a,c_sanjiaoxing_b,c_sanjiaoxing_c,s_chang_a,s_chang_b,s_zheng_a,s_yuan_r,s_sanjiaoxing_a,s_sanjiaoxing_h,v_changfangti_a,v_changfangti_b,v_changfangti_c,v_zhengfangti_a,v_yuanzhui_r,v_yuanzhui_h,v_yuanzhu_r,v_yuanzhu_h,sb_changfangti_a,sb_changfangti_b,sb_changfangti_c,sb_zhengfangti_a,sb_yuanzhu_r,sb_yuanzhu_h;
  cout<<"欢迎来到超级图形计算器！"<<endl;
  system("pause");
  system("cls");
  while(flag){
  	Sleep(1000);
  	cout<<"请问你要：1.计算周长；2.计算面积；3.计算体积；4.计算表面积；5.退出 ";
  	cin>>a;
  	switch(a){
  		case 1: 
  			cout<<"请问你要计算哪种图形的周长：";
  			cout<<"1.长方形；2.正方形；3.圆；4.三角形 ";
  			cin>>b;
  			switch(b){
  				case 1: 
  					cout<<"请输入长方形的长：";
  					cin>>c_chang_a;
  					cout<<"请输入长方形的宽：";
  					cin>>c_chang_b;
  					cout<<"长方形的周长："<<c_changfangxing(c_chang_a,c_chang_b)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				case 2: 
  					cout<<"请输入正方形的边长：";
  					cin>>c_zheng_a;
  					cout<<"正方形的周长："<<c_zhengfangxing(c_zheng_a)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				case 3: 
  					cout<<"请输入圆的半径：";
					cin>>c_yuan_r;
					cout<<"圆的周长是："<<c_yuan(c_yuan_r)<<endl;
					system("pause");
  					system("cls");
					break;
				case 4: 
			    	cout<<"请输入三角形的第一条边：";
			    	cin>>c_sanjiaoxing_a;
			    	cout<<"请输入三角形的第二条边：";
			    	cin>>c_sanjiaoxing_b;
			    	cout<<"请输入三角形的第三条边：";
			    	cin>>c_sanjiaoxing_c;
			    	cout<<"三角形的周长是："<<c_sanjiaoxing(c_sanjiaoxing_a,c_sanjiaoxing_b,c_sanjiaoxing_c)<<endl;
			    	system("pause");
  					system("cls");
			    	break;
			    default: 
			    	cout<<"输入错误，请重新输入！"<<endl;
			    	Sleep(2000);
			    	system("pause");
			    	break;
				}
		break;
  		case 2: 
  			cout<<"请问你要计算哪种图形的面积：";
  			cout<<"1.长方形；2.正方形；3.圆；4.三角形 ";
  			cin>>c;
  			switch(c){
  				case 1: 
  					cout<<"请输入长方形的长：";
  					cin>>s_chang_a;
  					cout<<"请输入长方形的宽：";
  					cin>>s_chang_b;
  					cout<<"长方形的面积："<<s_changfangxing(s_chang_a,s_chang_b)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				case 2: 
  					cout<<"请输入正方形的边长：";
  					cin>>s_zheng_a;
  					cout<<"正方形的面积："<<s_zhengfangxing(s_zheng_a)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				case 3: 
  					cout<<"请输入圆的半径：";
					cin>>s_yuan_r;
					cout<<"圆的面积是："<<s_yuan(s_yuan_r)<<endl;
					system("pause");
  					system("cls");
					break;
				case 4: 
  					cout<<"请输入三角形的底："; 
  					cin>>s_sanjiaoxing_a;
  					cout<<"请输入三角形的高：" ;
  					cin>>s_sanjiaoxing_h;
  					cout<<"三角形的面积是："<<s_sanjiaoxing(s_sanjiaoxing_a,s_sanjiaoxing_h)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				default: 
  					cout<<"输入错误，请重新输入！"<<endl;
  					Sleep(2000);
  					system("cls");
  					break;
  		break;
		  		}
		case 3: 
			cout<<"请问你要计算哪种图形的体积：";
			cout<<"1.长方体；2.正方体；3.圆锥；4.圆柱 "; 
			cin>>d;
			switch(d){
				case 1: 
					cout<<"请输入长方体的长：";
					cin>>v_changfangti_a;
					cout<<"请输入长方体的宽：";
					cin>>v_changfangti_b;
					cout<<"请输入长方体的高：";
					cin>>v_changfangti_c;
					cout<<"长方体的体积是："<<v_changfangti(v_changfangti_a,v_changfangti_b,v_changfangti_c)<<endl;
					system("pause");
  					system("cls");
					break;
				case 2: 
					cout<<"请输入正方体的棱长：";
					cin>>v_zhengfangti_a;
					cout<<"正方体的体积："<<v_zhengfangti(v_zhengfangti_a)<<endl;
					system("pause");
  					system("cls");
					break;
				case 3: 
					cout<<"请输入圆锥的底面半径：";
					cin>>v_yuanzhui_r;
					cout<<"请输入圆锥的高：";
					cin>>v_yuanzhui_h;
					cout<<"圆锥的体积："<<v_yuanzhui(v_yuanzhui_r,v_yuanzhui_h)<<endl;
					system("pause");
  					system("cls");
					break;
				case 4: 
					cout<<"请输入圆柱的底面半径：";
					cin>>v_yuanzhu_r;
					cout<<"请输入圆柱的高：";
					cin>>v_yuanzhui_h;
					cout<<"圆柱的体积："<<v_yuanzhu(v_yuanzhu_r,v_yuanzhu_h)<<endl;
					system("pause");
  					system("cls");
					break;
				default: 
					cout<<"输入错误，请重新输入！"<<endl;
					Sleep(2000);
					system("pause");
					break;
			    }
  		break;
  		case 4: 
  			cout<<"请问你要计算哪种图形的表面积：";
  			cout<<"1.长方体；2.正方体；3.圆柱 ";
  			cin>>e;
  			switch(e){
  				case 1: 
  					cout<<"请输入长方体的长：";
  					cin>>sb_changfangti_a;
  					cout<<"请输入长方体的宽：";
  					cin>>sb_changfangti_b;
  					cout<<"请输入长方体的高：";
  					cin>>sb_changfangti_c;
  					cout<<"长方体的表面积是："<<sb_changfangti(sb_changfangti_a,sb_changfangti_b,sb_changfangti_c);
  					system("pause");
  					system("cls");
  					break;
  				case 2: 
  					cout<<"请输入正方体的棱长：";
  					cin>>sb_zhengfangti_a;
  					cout<<"正方体的表面积："<<sb_zhengfangti(sb_zhengfangti_a)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				case 3: 
  					cout<<"请输入圆柱的底面半径：";
  					cin>>sb_yuanzhu_r;
  					cout<<"请输入圆柱的高：";
  					cin>>sb_yuanzhu_h;
  					cout<<"圆柱的表面积："<<sb_yuanzhu(sb_yuanzhu_r,sb_yuanzhu_h)<<endl;
  					system("pause");
  					system("cls");
  					break;
  				default: 
  					cout<<"输入错误，请重新输入！"<<endl;
  					Sleep(2000);
  					system("cls");
			  }
  			break;
  		case 5: 
  			flag=false;
  			break;
  		default: 
  			cout<<"输入错误，请重新输入！"<<endl;
  			Sleep(2000);
  			system("cls");
		
}

}
	return 0;	
}