I have doing competitive programming for 2 years.I solved all the DIV 2B problems, and then, I have been solving the DIV 2C problems topicwise. Unfortunately, I have stuck between the 1300- 1500 level for the two years. I am feeling very discouraged. Can you guys please suggest me what am I doing wrong? How should I practice?
I can recommend the a2oj rating ladders. The first problems are easy, but they get harder quickly.
I can suggest a simple method that worked for me. After each contest, upsolve all the problems that you haven't solved (that includes D, E as well). If you can't figure out the solution by yourself, read the editorial, understand the solution and then code it. Don't stop until you've solved all the problems from this contest. If you keep to this procedure, in time you'll be able to solve harder problems.