Why doesn't a+++++b work?

Question

int main ()
{
   int a = 5,b = 2;
   printf(\"%d\",a+++++b);
   return 0;
}

This code gives the following error:

error: lval

Answer 1

printf("%d",a+++++b); is interpreted as (a++)++ + b according to the Maximal Munch Rule^!.

++ (postfix) doesn't evaluate to an lvalue but it requires its operand to be an lvalue.

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