How to make it so that you can only break blocks placed after a game starts

Me and my friends are attempting to recreate bedwars on a small server that we own using command blocks. We have a pretty good idea of how we're going to do everything, except for the fact that, we don't want players to be able to break blocks from de map, only blocks placed by other players and the beds. How would I go about doing this?

Note: I am using 1.8

Solution 1:

A rudimentary way to do this without a plugin is to only set all players to adventure mode and make all the tools be able to only break blocks that players have access to, for example

/give @p minecraft:diamond_pickaxe 1 0 {CanDestroy:["minecraft:wool", "minecraft:bed"], HideFlags:8}

so players in adventure mode can break wool and beds, hope this helps