Adapted from this blog: https://codeforces.com/blog/entry/68809

How to use debug.h

Place the file in /usr/local/include for Mac For Windows or Linux, put it wherever you have bits/stdc++.h located

Put #include<debug.h> at the top of your cpp file

Usage:

vector<int> a = {1, 3, 5};
debug(a)

// prints a = {1, 3, 5} to cerr

For online judges, you can use:

#ifndef ONLINE_JUDGE
#include<debug.h>
#else
#define debug(...)
#endif

Otherwise, replace the first line with #ifdef VAR where you define VAR with -D VAR