foo.cc:47:13: error: stray '\357' in program
     return 0；
             ^
foo.cc:47:14: error: stray '\274' in program
     return 0；
              ^
foo.cc:47:15: error: stray '\233' in program
     return 0；
               ^
foo.cc: In function 'int main()':
foo.cc:48:1: error: expected ';' before '}' token
 }
 ^
foo.cc:35:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld%lld",&n,&m);
     ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:38:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld%lld%lld",&k,&l,&r);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。