These leetcode problems are similar to the problems found in grokking-the-coding-interview. Trying these leetcode problems after learning the patterns in grokking is worthwhile practice. The main advantage of grokking is a detailed explanation per problem and grouping problems under common patterns.
grokking can be permanently bought from here. Lifetime access is $79, but 20% off coupons frequently appear on the site. Subscription based access through educative.io is another option.