towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:24:25: warning: conversion to 'int' from '__gnu_cxx::__normal_iterator<int*, std::vector<int> >::difference_type {aka long int}' may alter its value [-Wconversion]
x=max_element(ALL(dis))-dis.begin();
~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
towns.cpp:28:23: warning: conversion to 'int' from '__gnu_cxx::__normal_iterator<int*, std::vector<int> >::difference_type {aka long int}' may alter its value [-Wconversion]
y=max_element(ALL(a))-a.begin();
~~~~~~~~~~~~~~~~~~~^~~~~~~~~~
towns.cpp:18:28: warning: unused parameter 'sub' [-Wunused-parameter]
int hubDistance(int N, int sub)
^~~