foo.c: In function 'main':
foo.c:4:9: error: declaration for parameter 'b' but no such parameter
    4 | int x,a,b;
      |         ^
foo.c:4:7: error: declaration for parameter 'a' but no such parameter
    4 | int x,a,b;
      |       ^
foo.c:4:5: error: declaration for parameter 'x' but no such parameter
    4 | int x,a,b;
      |     ^
foo.c:9:1: error: expected '}' before 'else'
    9 | else if(x>>a<<b)
      | ^~~~
foo.c:17:1: error: expected declaration or statement at end of input
   17 | }
      | ^