foo.cc: In function 'int main()':
foo.cc:87:7: warning: unused variable 'j' [-Wunused-variable]
 int i,j,a,b;char cc;
       ^
foo.cc:90:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d%d",&n,&m);
 ~~~~~^~~~~~~~~~~~~~

正在同步测试数据，请稍后
自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。