refencing complex numbers with the Ch compiler

I am using a Ch compiler..
I came to know , that this is how we can access the real and imaginary parts of a complex number in this compiler...

Code:

    complex sz2;
    printf("sz2 = %f, %f\n", real(sz2),  imag(sz2));

when i use real() and imag() in my compiler , I get the following messages :

Code:

  fourier_pc_1d.o(.text+0x157): In function `main':
: undefined reference to `imag'
fourier_pc_1d.o(.text+0x181): In function `main':
: undefined reference to `real'

Can anyone tell me which library to file to include to get rid of this message?

Which library does the manual page for those two functions tell you to include?

silly mistake sorted it out..