src.c:1:3: error: initializer element is not constant
x=input();
^
src.c:2:3: error: initializer element is not constant
y=input();
^
src.c:3:3: error: initializer element is not constant
z=input();
^
src.c:4:5: error: initializer element is not constant
sum=x y z;
^
src.c:5:7: error: expected declaration specifiers or '...' before string constant
print("sum= ");
^