/in/foo.cc: In function 'int main()':
/in/foo.cc:6:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&V,&N);
                     ^
/in/foo.cc:8:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&v);
                 ^