/in/foo.cc: In function 'int calf(std::vector<std::vector<int> >&, int, int)':
/in/foo.cc:22:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int cals(std::vector<std::vector<int> >&, int, int)':
/in/foo.cc:36:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^