Exactly the the title says, I currently keep track of the problems I can't solve. However, even though I had done more than 50 1700 rated problems sometimes I still struggle... so should I redo the problems I can't solve or just solve new problems until I'm comfortable with this rating? Thank you!
you can try new problems. By the way,watching nailong can help a lot !
So you should usually read editorial if you cannot solve a problem at last.