Why am I getting this error: “data definition has no type or storage class”?

It looks like the line

head = (Node*) malloc( sizeof( Node ) ); //line 21

is outside the main() function. You can’t do that, because you can’t execute code outside functions. The only thing you can do at global scope is declaring variables. Just move it inside the main() or any other function, and the problem should go away.

(PS: Take a look at this question on why you shouldn’t type-cast malloc)

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