/in/foo.cc: In function 'int add(int, int)':
/in/foo.cc:9:68: warning: no return statement in function returning non-void [-Wreturn-type]
 int add(int a,int b){for(int i=a+1;i<=n+1;i+=i&-i)c[i]=max(c[i],b);}
                                                                    ^