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  • AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
  • AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
  • AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
  • AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
  • USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
  • Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
  • AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
  • DMOJ: DMOJ [contest name (if applicable)] [problem number (e.g. P1)] - [Problem name], Ex: DMOJ Yet Another Contest 3 P1 - Shell Swap Scam
  • USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
16183 DMOJ COCI '09 Contest 6 #4 Xor
16182 DMOJ COCI '09 Contest 6 #3 Dosadan
16181 DMOJ COCI '09 Contest 6 #2 Natjecanje
16180 DMOJ COCI '09 Contest 6 #1 Kajak
16179 DMOJ COCI '09 Contest 5 #6 Chuck
16178 DMOJ COCI '09 Contest 5 #5 Program
16177 DMOJ COCI '09 Contest 5 #4 Zuma
16176 DMOJ COCI '09 Contest 5 #3 Kletva
16175 DMOJ COCI '09 Contest 5 #2 Cudoviste
16174 DMOJ COCI '09 Contest 5 #1 Sok
16173 DMOJ COCI '09 Contest 4 #6 Palacinke
16172 DMOJ COCI '09 Contest 4 #5 Kaboom
16171 DMOJ COCI '09 Contest 4 #4 Ograda
16170 DMOJ COCI '09 Contest 4 #3 IKS
16169 DMOJ COCI '09 Contest 4 #2 Planina
16168 DMOJ COCI '09 Contest 4 #1 Autori
16167 DMOJ COCI '09 Contest 3 #6 Planete
16166 DMOJ COCI '09 Contest 3 #5 Patuljci
16165 DMOJ COCI '09 Contest 3 #4 Razgovori
16164 DMOJ COCI '09 Contest 3 #3 Sort
16163 DMOJ COCI '09 Contest 3 #2 Slatkisi
16162 DMOJ COCI '09 Contest 3 #1 Filip
16161 DMOJ COCI '09 Contest 2 #6 Pasijans
16160 DMOJ COCI '09 Contest 2 #5 Poslozi
16159 DMOJ COCI '09 Contest 2 #4 Vuk
16158 DMOJ COCI '09 Contest 2 #3 Kutevi
16157 DMOJ COCI '09 Contest 2 #2 Rimski
16156 DMOJ COCI '09 Contest 2 #1 Faktor
16155 DMOJ COCI '09 Contest 1 #6 Aladin
16154 DMOJ COCI '09 Contest 1 #5 Genijalac
16153 DMOJ COCI '09 Contest 1 #4 Mali
16152 DMOJ COCI '09 Contest 1 #3 Dobra
16151 DMOJ COCI '09 Contest 1 #2 Domino
16150 DMOJ COCI '09 Contest 1 #1 Note
16149 DMOJ COCI '08 Contest 6 #6 Slicice
16148 DMOJ COCI '08 Contest 6 #5 Dostava
16147 DMOJ COCI '08 Contest 6 #4 Cuskija
16146 DMOJ COCI '08 Contest 6 #3 Nered
16145 DMOJ COCI '08 Contest 6 #2 Bazen
16144 DMOJ COCI '08 Contest 6 #1 Buka
16143 DMOJ COCI '08 Contest 5 #6 Kruska
16142 DMOJ COCI '08 Contest 5 #5 Tresnja
16141 DMOJ COCI '08 Contest 5 #4 Lubenica
16140 DMOJ COCI '08 Contest 5 #3 Jagoda
16139 DMOJ COCI '08 Contest 5 #2 Jabuka
16138 DMOJ COCI '08 Contest 5 #1 Ljesnjak
16137 DMOJ COCI '08 Contest 4 #6 Periodni
16136 DMOJ COCI '08 Contest 4 #5 Trezor
16135 DMOJ COCI '08 Contest 4 #4 Slikar
16134 DMOJ COCI '08 Contest 4 #3 Rot
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