Mã chấm: 268625

Main.cc: In function ‘int main()’:
Main.cc:16:9: error: ‘k’ was not declared in this scope
         k++;
         ^
Main.cc:6:10: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lf", &c);
     ~~~~~^~~~~~~~~~~