Greetings,

I have been thinking about the cheating problem and I have a suggestion. CF should add phone number verification and allow only those users who have verified their phone number to participate in contests.

Phone numbers are not as easily available as emails, which will create a hindrance for making new accounts after a ban. Additionally, if anyone uses another person's phone number, they will be paranoid that the owner of the phone number can take over their account at any moment.