To guess the solution for a greedy problem, brings some benefit? I want to improve my greedy skills, and i'm doing problems, but a lot of the problem that I've solved I only guess the greedy idea, If I get WA, I guess again... It that help? Or are there better ways to improve greedy that only doing problems?

What is the key for the successful of European and Asian teams?
I'm from Latin American and I know that the best teams train a lot
Maybe 10 years, but they never can be successful in Word Final or IOI
Why that difference?

If I want to build a graph when the input is a set of points
and an edge exists if the distance between two points is less than
some value x, what is the best way to construct the graph?

Hi codeforces, I need to improve my Math Skills
I want to become a engineer but i've been doing some math test and I've failed
The principal topic is numerical reasoning and numerical series progression
Can you give me some resources that really helps to improve those topics.


Thanks in advance!