/in/foo.c: In function 'main':
/in/foo.c:4:2: error: 'a' undeclared (first use in this function)
    4 | {a = int(input())
      |  ^
/in/foo.c:4:2: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:4:6: error: expected expression before 'int'
    4 | {a = int(input())
      |      ^~~