strange_device.cpp: In function 'int main()':
strange_device.cpp:18:29: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 2 has type 'std::set<std::pair<long long unsigned int, long long unsigned int> >::size_type {aka long unsigned int}' [-Wformat=]
     printf("%llu",res.size());
                   ~~~~~~~~~~^
strange_device.cpp:8:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%llu%llu%llu",&n,&a,&b);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:12:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%llu%llu",&t,&l);
         ~~~~~^~~~~~~~~~~~~~~~~~