foo.c: In function 'main':
foo.c:6:3: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
   scanf("%c",&s[i]);
   ^~~~~
foo.c:6:3: warning: incompatible implicit declaration of built-in function 'scanf'
foo.c:6:3: note: include '<stdio.h>' or provide a declaration of 'scanf'
foo.c:21:3: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
   printf("Right\n");
   ^~~~~~
foo.c:21:3: warning: incompatible implicit declaration of built-in function 'printf'
foo.c:21:3: note: include '<stdio.h>' or provide a declaration of 'printf'
foo.c:26:4: warning: incompatible implicit declaration of built-in function 'printf'
    printf("%c",s[i]);
    ^~~~~~
foo.c:26:4: note: include '<stdio.h>' or provide a declaration of 'printf'

自豪的采用jd5进行评测(github.com/masnn/jd5)

{"receive":"2020-02-23T06:57:14.387Z","handle":"2020-02-23T06:57:14.387Z","cache_start":"2020-02-23T06:57:14.387Z","read_cases":"2020-02-23T06:57:14.534Z","judge":"2020-02-23T06:57:14.535Z","done":"2020-02-23T06:57:14.965Z"}