/in/foo.cc: In function 'int addedge(int, int, int)':
/in/foo.cc:23:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int init()':
/in/foo.cc:30:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int spfa()':
/in/foo.cc:53:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int dp(int, int)':
/in/foo.cc:76:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int work()':
/in/foo.cc:122:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^