prog.c: In function ‘main’:
prog.c:12:16: error: ‘h’ undeclared (first use in this function)
scanf ("%f", &h);
^
prog.c:12:16: note: each undeclared identifier is reported only once for each function it appears in
prog.c:8:16: warning: unused variable ‘c’ [-Wunused-variable]
float x,y,a,b,c;
^