[toc] # Codeforces ## Elo 800 ### Daily challenge August SPyofgame <details><summary>Info</summary> ![image](https://hackmd.io/_uploads/r1BO49oPxl.png) </details> ### Contest STL Star <details><summary>Info</summary> Trong này có 13 bài 800, 3 bài còn lại để ở mục khác ![image](https://hackmd.io/_uploads/Hyqoe0hvgl.png) </details> ### 2126A - Only one digit <details><summary>Info</summary> https://codeforces.com/problemset/problem/2126/A ![image](https://hackmd.io/_uploads/HJrQfJjwxe.png) </details> ### 2123B - Tournament <details><summary>Info</summary> https://codeforces.com/problemset/problem/2123/B ![image](https://hackmd.io/_uploads/Hytjzkswxe.png) </details> ### 2117A - False Alarm <details><summary>Info</summary> https://codeforces.com/problemset/problem/2117/A ![image](https://hackmd.io/_uploads/H1Z4XyjPel.png) </details> ### 2109A - It's time to duel <details><summary>Info</summary> https://codeforces.com/problemset/problem/2109/A ![image](https://hackmd.io/_uploads/HJ-oQJiPel.png) </details> ### 2123A - Blackboard game <details><summary>Info</summary> https://codeforces.com/problemset/problem/2123/A ![image](https://hackmd.io/_uploads/r1QYnVoDgg.png) </details> ### 1520B - Ordinary Numbers <details><summary>Info</summary> https://codeforces.com/problemset/problem/1520/B ![image](https://hackmd.io/_uploads/HJ1QSKpvll.png) </details> ### 2126B - No Casino In the Mountain <details><summary>Info</summary> https://codeforces.com/problemset/problem/2126/B ![image](https://hackmd.io/_uploads/r1jDzYWOle.png) </details> ### 2094A - Trippi Troppi <details><summary>Info</summary> https://codeforces.com/problemset/problem/2094/A ![image](https://hackmd.io/_uploads/HJH6N_QOex.png) </details> ## Elo 900 ### New's year number <details><summary>Info</summary> https://codeforces.com/problemset/problem/1475/B ![image](https://hackmd.io/_uploads/BJRUt9Tvxx.png) </details> ### Radio Station <details><summary>Info</summary> https://codeforces.com/problemset/problem/918/B ![image](https://hackmd.io/_uploads/Hk3w-Xx_lg.png) </details> ## Elo 1300 ### Registration System <details><summary>Info</summary> https://codeforces.com/problemset/problem/4/C ![image](https://hackmd.io/_uploads/H1hVfXxuxe.png) </details> ## Elo 1400 ### T-shirts Buying <details><summary>Info</summary> https://codeforces.com/problemset/problem/799/B ![image](https://hackmd.io/_uploads/rknKMmgOxx.png) </details> # CSES ## Graph Algorithm ### Couting Rooms <details><summary>Info</summary> https://cses.fi/problemset/task/1192/ ![image](https://hackmd.io/_uploads/SJJBNyjvll.png) </details> ### Labyrinth <details><summary>Info</summary> https://cses.fi/problemset/task/1193/ ![image](https://hackmd.io/_uploads/S1MuhZoDlg.png) </details> # VNOI ### Chọn bi <details><summary>Info</summary> https://oj.vnoi.info/problem/nd_thpt_2122_b ![image](https://hackmd.io/_uploads/HyVVSOQdle.png) </details> # EUIOJ ### Abundant Number <details><summary>Info</summary> https://oj.eiu.edu.vn/problem/abundant_number ![image](https://hackmd.io/_uploads/BymDCdQdgl.png) </details>