foo.c:1:1: warning: data definition has no type or storage class
 x = int(input())
 ^
foo.c:1:1: warning: type defaults to 'int' in declaration of 'x' [-Wimplicit-int]
foo.c:1:5: error: expected expression before 'int'
 x = int(input())
     ^~~

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)