/in/main.c: In function 'main':
/in/main.c:16:11: error: implicit declaration of function 'time' [-Werror=implicit-function-declaration]
     srand(time(NULL));
           ^~~~
/in/main.c:14:12: error: variable 'rate' set but not used [-Werror=unused-but-set-variable]
     double rate;
            ^~~~
/in/main.c:15:13: error: 'r2' is used uninitialized in this function [-Werror=uninitialized]
     rate=(r2+k)/(r1+r2+k);
          ~~~^~~
/in/main.c:15:13: error: 'k' is used uninitialized in this function [-Werror=uninitialized]
/in/main.c:15:20: error: 'r1' is used uninitialized in this function [-Werror=uninitialized]
     rate=(r2+k)/(r1+r2+k);
                  ~~^~~
cc1: all warnings being treated as errors