Why is C++ result rounded?

Question

Programming

a=Edit1->Text;
b=Edit2->Text;
double m=StrToInt(a);
double n=StrToInt(b);
double o=StrToInt(Edit4->Text);
double sina=sin(o*PI/180);
double sinb=n/(m/sina);
B=asin(sinb);
B=B*180/PI;
Edit5->Text = B;
tested with values ​​a=5 b=6 A=30. the result is 38, although it actually turns out to be 36.8698976458 why is it rounded off?

Answer 1

Perhaps you have somewhere where int is used during calculations, look at it more carefully. What type B?

Answer 2

I guessed on the cards - it did not help. Threw bones - too. I asked the stars for an answer. The stars are interested - is it because you divide by 180? :)