foo.cc: In function 'int main()':
foo.cc:6:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d",&a,&b);
         ~~~~~^~~~~~~~~~~~~~~
foo.cc:13:11: warning: 't' may be used uninitialized in this function [-Wmaybe-uninitialized]
     printf("%d",t+1);
     ~~~~~~^~~~~~~~~~

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