Explain macro substitution directive in c programming language?

Answer:


e.g.   #define pie 3.14 void main() { float r=3,area; area=3*r*pie; printf(“%f”,area); getch(); }   Before the starting of actual compilation an intermediate is formed which is:   We can see only in place of pie, 3.14 has pasted. If is very long or we want to write in next line, end first line by \. e.g.   #define word c is powerful \ language.