Pairs Format: One-Based or Zero-Based Coordinate System?

Hello,

Given that the [pairs format](https://github.com/4dn-dcic/pairix/blob/master/pairs_format_specification.md) requires only one position per contact, it seems that the format implicitly uses a [One-Based Coordinate System](https://www.biostars.org/p/84686/) for locating contacts. However, I still wanted to double-check to be on the safe side.

Thanks!