2019CCPC湖南全国邀请赛(广东省赛、江苏省赛) C.Chika and Friendly Pairs
ProblemDescriptionChikagivesyouanintegersequencea1,a2,…,anandmtasks.Foreachtask,youneedtoanswerthenumberof"friendlypairs"inagiveninterval.friendlypair:fortwointegersaiandaj,ifi#include#include#include