foo.cc: In function 'bool sushu(int)':
foo.cc:18:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.cc: In function 'int main()':
foo.cc:38:19: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<m<<"="<<b<<"+"<<a;
                   ^~~

[Hydro](https://hydro.ac)提供评测服务