uses crt;
var n,a,b,c:real;
begin
clrscr;
writeln('MOI BAN CHON HINH CAN TINH DIEN TICH: ');
writeln('1. Hinh vuong.');
writeln('2. Hinh chu nhat.');
writeln('3. Hinh tron.');
writeln('4. Hinh tam giac.');
writeln('5. Hinh thang.');
readln(n);
if n=1 then
begin
write('Canh:');readln(a);
writeln('Dien tich: ',a*a:0:2);
end else
if n=2 then
begin
write('Chieu dai:');readln(a);
write('Chieu rong:');readln(b);
writeln('Dien tich: ',a*b:0:2);
end else
if n=3 then
begin
write('Ban king:');readln(a);
writeln('Dien tich: ',a*a*3.14:0:2);
end else
if n=4 then
begin
write('Duong cao:');readln(a);
write('Day:');readln(b);
writeln('Dien tich: ',a*b/2:0:2);
end else
if n=5 then
begin
write('Day tren:');readln(a);
write('Day duoi:');readln(b);
write('Duong cao:');readln(c);
writeln('Dien tich: ',c/2*(a+b):0:2);
end;
readln
end.
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Test: