Program Tinh_dien_tich;
Uses crt;
Var chon: Char;
Procedure Hinh_tam_giac;
Var a, h, s: Real;
Begin
Wite ('nhap canh huyen, chieu cao hinh tam giac ') ; readln (a, h) ;
S: =a*h/2;
Write ('dien tich hinh ta m giac la: ', s: 5) ;
End;
Procedure Hinh_tron;
Uses crt;
Var s, r: Real;
Begin
Write ('nhap ban kinh: ') ; readln (r) ;
S: =3.14*r*r;
Write ('dien tich cua hinh tron la: ', s: 5: 2) ;
End;
Procedure Hinh_vuong;
Uses crt;
Var a, s: Real;
Begin
Write ('nhap chieu dai canh: ') ; readln (a) ;
S: =a*a;
Write ('dien tich hinh vuong: ', s: 5: 2) ;
End;
Procedure Hinh_chu_nhat;
Uses crt;
Var a, b, s: Real;
Begin
Write ('nhap chieu dai: ') ; readln (a) ;
Write ('nhap chieu rong: ') ; readln (b) ;
S: =a*b;
Write ('dien tich hinh chu nhat la: ', s: 6: 2) ;
End;
Procedure Hinh_thang;
Uses crt;
Var a, b, h, s: Real;
Begin
Write ('nhap day lon: ') ; readln (a) ;
Write ('nhap day nho: ') ; readln (b) ;
Write ('nhap chieu cao: ') ; readln (h) ;
S: =((a+b) *h) /2;
Write ('dien tich hinh thang la: ', s: 6: 2) ;
End;
{phan chuong trinh chinh}
Begin
Clrscr;
Writeln ('0. Thoat') ;
Writeln ('1. Dien tich hinh tam giac) ;
Writeln ('2. Dien tich hinh tron) ;
Writeln ('3. Dien tich hinh vuong) ;
Writeln ('4. Dien tich hinh chu nhat) ;
Writeln ('5. Dien tich hinh thang) ;
Writeln (nhan mot phim de chon') ;
Readln (chon) ;
Case chon of
"0" : Exit;
"1" : Hinh_tam_giac;
"2" : Hinh_tron;
"3" : Hinh_vuong;
"4" : Hinh_chu_nhat;
"5" : Hinh_thang;
Else write ('sai') ;
End;
Readln;
End .