/in/ex1.c: In function 'main':
/in/ex1.c:10:16: warning: variable 'c2' set but not used [-Wunused-but-set-variable]
     complex c1,c2,c3;
                ^~
/in/ex1.c:10:13: warning: variable 'c1' set but not used [-Wunused-but-set-variable]
     complex c1,c2,c3;
             ^~
/in/ex1.c:41:9: warning: 'c3.imaginary' may be used uninitialized in this function [-Wmaybe-uninitialized]
         printf("%d%di",c3.real,c3.imaginary);
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/in/ex1.c:41:9: warning: 'c3.real' may be used uninitialized in this function [-Wmaybe-uninitialized]