/in/foo.cc: In function 'bool cmp(li, li)':
/in/foo.cc:24:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     return x.x<y.x||x.x==y.x&&x.y<y.y;
                     ~~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'int bfs(int)':
/in/foo.cc:72:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:95:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     if(check())return 0;memset(vis,1,sizeof(vis));what=0;
     ^~
/in/foo.cc:95:25: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
     if(check())return 0;memset(vis,1,sizeof(vis));what=0;
                         ^~~~~~
/in/foo.cc:77:9: warning: unused variable 'i' [-Wunused-variable]
     int i,j,k,b,c;
         ^
/in/foo.cc:77:11: warning: unused variable 'j' [-Wunused-variable]
     int i,j,k,b,c;
           ^
/in/foo.cc:77:13: warning: unused variable 'k' [-Wunused-variable]
     int i,j,k,b,c;
             ^
/in/foo.cc:77:15: warning: unused variable 'b' [-Wunused-variable]
     int i,j,k,b,c;
               ^
/in/foo.cc:77:17: warning: unused variable 'c' [-Wunused-variable]
     int i,j,k,b,c;
                 ^