What do "Mac Ads Cleaner" and "Mac App Cleaner" do while installed?
You ran into a scam - that was not an actual Flash Player update, it was just a malware installer made to look like Adobe Flash Player. People are so used to updating Flash every other day, so a web site offering an upgrade doesn't set off any alarms.

The programs that got installed are search hijackers. They bring up pages offering other fake programs, or even send you to a page that insists you have a virus, which includes a handy 800 number to call to remove it. This is a scam - the "support" company will remote into your system, probably steal personal info such as banking files, then charge you $500 for their "service." Fake, fake, fake.

Go to malwarebytes.org and download the free Mac version of AntiMalware. It will scan for and remove the remnants of those junk apps.

Next time you get a prompt to update Flash, use the applet in System Preferences or get the update direct from adobe.com. If the site still says you need to update, it's a scam and you should run screaming.