Hi everyone, i hope you are doing great <3 ;). I want some help here to improve my skills in problem solving. I am writing in java and i love it, but there are some problems require some math skills and graph theory, So, can anyone help me which topics of math and graphs should study please some resources... cause i want to be orange in someday <3 ;), but with my skills right now i can't return to pupil again, so advice me how should do in contest, detect a target like i will solve first 3 and focus on that or switch between problems because sometimes i stuck in a problem and can't leave it , so that make my rate go down and make me disappointed , So, i need some help here. Thanks in advance <3 ;)