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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1528 | Searching Rectangles | binary search constructive algorithms interactive | Statement | B | Codeforces Round 371 (Div. 1) {713} | PROGRAMMING | Codeforces Round #371 Editorial | 2200 | |
| 222 | Verifying Kingdom | binary search divide and conquer interactive trees | Statement | E | VK Cup 2017 - Round 2 {772} | PROGRAMMING | VK Cup Round 2 + Codeforces Round #409 Tutorial | 3200 | |
| 1817 | Glad to see you! | binary search interactive | Statement | B | Codeforces Round 415 (Div. 1) {809} | PROGRAMMING | 52099 | 2200 | |
| 1388 | The penguin's game | binary search constructive algorithms interactive | Statement | E | Codeforces Round 427 (Div. 2) {835} | PROGRAMMING | 2400 | ||
| 2083 | Mahmoud and Ehab and the binary string | binary search divide and conquer interactive | Statement | D | Codeforces Round 435 (Div. 2) {862} | PROGRAMMING | Codeforces round #435 editorial | 2000 | |
| 2331 | Ithea Plays With Chtholly | binary search constructive algorithms games greedy interactive | Statement | B | Codeforces Round 449 (Div. 1) {896} | PROGRAMMING | Codeforces Round #449 Editorial | 2000 | |
| 563 | Guess two numbers | binary search interactive | Statement | C | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 2800 | |
| 6456 | Rocket | binary search interactive | Statement | B | Codeforces Round 499 (Div. 1) {1010} | PROGRAMMING | 60851 | 1800 | |
| 2144 | The hat | binary search interactive | Statement | B | Codeforces Round 503 (by SIS, Div. 1) {1019} | PROGRAMMING | 61161 | 2200 | |
| 821 | Hidden Bipartite Graph | binary search constructive algorithms dfs and similar graphs interactive | Statement | E | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2700 | |
| 2611 | Subway Pursuit | binary search interactive probabilities | Statement | B | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2100 | |
| 3299 | Dwarves, Hats and Extrasensory Abilities | binary search constructive algorithms geometry interactive | Statement | C | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | 1900 | ||
| 3568 | Game with modulo | binary search constructive algorithms interactive | Statement | B | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 2000 | |
| 3247 | Arithmetic Progression | binary search interactive number theory probabilities | Statement | E | Codeforces Round 538 (Div. 2) {1114} | PROGRAMMING | Codeforces Round #538 (Div. 2) Editorial | 2100 | |
| 616 | Legendary Tree | binary search interactive trees | Statement | E | Codeforces Round 542 [Alex Lopashev Thanks-Round] (Div. 1) {1129} | PROGRAMMING | 65520 | 3000 | |
| 1793 | Serval and Snake | binary search brute force interactive | Statement | E | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 2100 | |
| 232 | Strange device | binary search interactive math trees | Statement | E | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 3300 | |
| 93 | Шардирование постов | *special binary search interactive | Statement | F | VK Cup 2019 - Квалификация (Engine) {1275} | PROGRAMMING | 3000.0 | ||
| 982 | Find a Gift | binary search interactive probabilities | Statement | G | Educational Codeforces Round 87 (Rated for Div. 2) {1354} | PROGRAMMING | 77593 | 2600 | |
| 4462 | Guess The Maximums | binary search divide and conquer implementation interactive math | Statement | D | Codeforces Round 646 (Div. 2) {1363} | PROGRAMMING | 2000.0 | 78202 | 2100 |
| 1839 | The Hidden Pair (Easy Version) | binary search dfs and similar graphs interactive shortest paths trees | Statement | F1 | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 2000.0 | Editorial — Codeforces Round #651 | |
| 1725 | The Hidden Pair (Hard Version) | binary search dfs and similar graphs interactive shortest paths trees | Statement | F2 | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 1250.0 | Editorial — Codeforces Round #651 | |
| 354 | Colors | *special binary search constructive algorithms interactive | Statement | A | Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} | PROGRAMMING | T | ||
| 359 | The Potion of Great Power | *special binary search data structures graphs interactive sortings two pointers | Statement | A | Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} | PROGRAMMING | CEOI 2020 Online Mirror — Day 2 Tutorial | ||
| 1922 | Deleting Numbers | binary search brute force interactive number theory | Statement | E | Codeforces Round 670 (Div. 2) {1406} | PROGRAMMING | 2750.0 | Codeforces Round #670 (Div. 2) Editorial | |
| 129 | Rotary Laser Lock | binary search interactive | Statement | H | Codeforces Raif Round 1 (Div. 1 + Div. 2) {1428} | PROGRAMMING | 4000.0 | Codeforces Raif Round 1 Editorial | |
| 247 | The Riddle of the Sphinx | binary search data structures data structures interactive | Statement | I | Good Bye 2020 {1466} | PROGRAMMING | 4000.0 | Good Bye 2020 Editorial | |
| 1464 | Strange Shuffle | binary search brute force constructive algorithms interactive probabilities | Statement | C | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 1000.0 | 86464 | |
| 13310 | Searching Local Minimum | binary search interactive ternary search | Statement | A | Codeforces Round 700 (Div. 1) {1479} | PROGRAMMING | 500.0 | Editorial of Codeforces Round #700 | |
| 352 | Vabank | binary search interactive | Statement | G | Технокубок 2021 - Финал {1482} | PROGRAMMING | 3500.0 | Technocup 2021: Final Round and Codeforces Round #709 — tutorial | |
| 41 | Vabank | binary search interactive | Statement | E | Codeforces Round 709 (Div. 1, based on Technocup 2021 Final Round) {1483} | PROGRAMMING | 2500.0 | Technocup 2021: Final Round and Codeforces Round #709 — tutorial | |
| 14450 | Guessing the Greatest (easy version) | binary search interactive | Statement | C1 | Codeforces Round 703 (Div. 2) {1486} | PROGRAMMING | 750.0 | Codeforces Round #703 (Div. 2) Editorial | |
| 10202 | Guessing the Greatest (hard version) | binary search interactive | Statement | C2 | Codeforces Round 703 (Div. 2) {1486} | PROGRAMMING | 750.0 | Codeforces Round #703 (Div. 2) Editorial | |
| 1153 | Magnets | binary search constructive algorithms interactive | Statement | F | Codeforces Global Round 13 {1491} | PROGRAMMING | 2000.0 | Codeforces Global Round 13 Editorial | |
| 710 | Baby Ehab's Hyper Apartment | binary search graphs interactive sortings | Statement | E | Codeforces Round 716 (Div. 2) {1514} | PROGRAMMING | 2500.0 | Codeforces round #716 editorial | |
| 3399 | Guess the K-th Zero (Hard version) | binary search data structures interactive | Statement | F2 | Codeforces Round 719 (Div. 3) {1520} | PROGRAMMING | Editorial | ||
| 14711 | Guess the K-th Zero (Easy version) | binary search interactive | Statement | F1 | Codeforces Round 719 (Div. 3) {1520} | PROGRAMMING | Editorial | ||
| 3129 | Gold Transfer | binary search data structures greedy interactive trees | Statement | E | Educational Codeforces Round 110 (Rated for Div. 2) {1535} | PROGRAMMING | 91481 | ||
| 470 | Guess the Perimeter | binary search interactive number theory | Statement | H | Codeforces Global Round 15 {1552} | PROGRAMMING | 2750.0 | Editorial of Global Round 15 | |
| 4026 | Guess the Permutation | binary search combinatorics interactive math | Statement | D | Technocup 2022 - Elimination Round 2 {1584} | PROGRAMMING | 1500.0 | Editorial for Technocup 2022 — Elimination Round 2 and Codeforces Round #755 (Div. 1, Div. 2) | 2000 |
| 2652 | Hemose in ICPC ? | binary search dfs and similar divide and conquer interactive math number theory trees | Statement | D | Codeforces Round 746 (Div. 2) {1592} | PROGRAMMING | 2000.0 | 95583 | |
| 3865 | Interacdive Problem | binary search constructive algorithms interactive | Statement | F | Codeforces Round 764 (Div. 3) {1624} | PROGRAMMING | Codeforces Round #764 (Div. 3) Editorial | ||
| 2535 | notepad.exe | binary search constructive algorithms greedy interactive | Statement | E | Codeforces Global Round 20 {1672} | PROGRAMMING | 1500.0 | Global Round 20 Editorial | 2200 |
| 5048 | Guess The String | binary search brute force constructive algorithms dsu interactive | Statement | D | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 12453 | Fixed Point Guessing | binary search constructive algorithms interactive | Statement | D | Codeforces Round 803 (Div. 2) {1698} | PROGRAMMING | 1500.0 | Codeforces Round #803 (Div. 2) Editorial | |
| 1785 | Joking (Easy Version) | binary search bitmasks constructive algorithms interactive ternary search | Statement | E1 | Codeforces Global Round 23 {1746} | PROGRAMMING | 2000.0 | Codeforces Global Round 23 Editorial | |
| 794 | Doremy's Perfect DS Class (Easy Version) | binary search interactive | Statement | G1 | Codeforces Global Round 24 {1764} | PROGRAMMING | 2000.0 | Codeforces Global Round 24 Editorial | |
| 724 | Doremy's Perfect DS Class (Medium Version) | binary search interactive | Statement | G2 | Codeforces Global Round 24 {1764} | PROGRAMMING | 500.0 | Codeforces Global Round 24 Editorial | |
| 618 | Doremy's Perfect DS Class (Hard Version) | binary search interactive | Statement | G3 | Codeforces Global Round 24 {1764} | PROGRAMMING | 500.0 | Codeforces Global Round 24 Editorial | |
| 504 | Hot and Cold | binary search interactive | Statement | H | 2022-2023 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1773} | PROGRAMMING | 2600 | ||
| 5898 | Bit Guessing Game | binary search bitmasks interactive | Statement | D | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 1500.0 | 111841 | |
| 17170 | Interview | binary search implementation interactive | Statement | E | Codeforces Round 859 (Div. 4) {1807} | PROGRAMMING | 114143 | ||
| 396 | Stuck Conveyor | binary search interactive | Statement | F | Codeforces Round 877 (Div. 2) {1838} | PROGRAMMING | 3000.0 | Codeforces Round #877 (Div. 2) Editorial | |
| 518 | Good Colorings | binary search constructive algorithms graphs interactive | Statement | E | Codeforces Round 905 (Div. 1) {1887} | PROGRAMMING | 2000.0 | Codeforces Round #905 (Div. 1, Div. 2, Div. 3) Editorial | |
| 2127 | ace5 and Task Order | binary search divide and conquer implementation interactive probabilities sortings | Statement | E | Codeforces Round 922 (Div. 2) {1918} | PROGRAMMING | 2500.0 | Codeforces Round #922 (Div. 2) Editorial | |
| 1215 | Catch the Mole(Easy Version) | binary search constructive algorithms data structures interactive trees | Statement | E1 | Codeforces Round 960 (Div. 2) {1990} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 1189 | Catch the Mole(Hard Version) | binary search data structures dfs and similar interactive trees | Statement | E2 | Codeforces Round 960 (Div. 2) {1990} | PROGRAMMING | 750.0 | Video Tutorial | |
| 14963 | Ruler (easy version) | binary search interactive ternary search | Statement | G1 | Codeforces Round 964 (Div. 4) {1999} | PROGRAMMING | Video Tutorial | ||
| 11489 | Ruler (hard version) | binary search interactive ternary search | Statement | G2 | Codeforces Round 964 (Div. 4) {1999} | PROGRAMMING | Video Tutorial | ||
| 13027 | Guess The Tree | binary search brute force greedy interactive trees | Statement | C | Codeforces Round 967 (Div. 2) {2001} | PROGRAMMING | 1500.0 | Video Tutorial | |
| 4127 | Asesino (Easy Version) | binary search constructive algorithms implementation interactive | Statement | D1 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 1750.0 | Codeforces Round 978 (Div 2) Editorial | |
| 475 | Penchick and Even Medians | binary search constructive algorithms interactive | Statement | F | Codeforces Round 987 (Div. 2) {2031} | PROGRAMMING | 3000.0 | Codeforces Round 987 (Div. 2) Editorial | |
| 6320 | Genokraken | binary search constructive algorithms data structures graphs interactive trees two pointers | Statement | D | Codeforces Round 983 (Div. 2) {2032} | PROGRAMMING | 1750.0 | Codeforces Round 983 (Div. 2) Editorial | |
| 1728 | Library of Magic | binary search bitmasks constructive algorithms interactive | Statement | G | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 1621 | Broken Queries | binary search bitmasks interactive | Statement | E | Codeforces Round 994 (Div. 2) {2049} | PROGRAMMING | 2250.0 | Codeforces Round #994 (Div. 2) Editorial | |
| 644 | Baudelaire (hard version) | binary search dfs and similar divide and conquer implementation interactive trees | Statement | G2 | Codeforces Round 1020 (Div. 3) {2106} | PROGRAMMING | Codeforces Round 1020 (Div. 3) Editorial | ||
| 1663 | Baudelaire (easy version) | binary search interactive trees | Statement | G1 | Codeforces Round 1020 (Div. 3) {2106} | PROGRAMMING | Codeforces Round 1020 (Div. 3) Editorial | ||
| 2462 | Needle in a Numstack | binary search brute force interactive math | Statement | D | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 2250.0 | Codeforces Round 1022 Editorial | |
| 124 | Inter Active (Hard Version) | binary search bitmasks constructive algorithms graphs implementation interactive math probabilities | Statement | G2 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2750.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 116 | Inter Active (Easy Version) | binary search constructive algorithms interactive interactive | Statement | G1 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2750.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 1787 | Interactive RBS (Hard Version) | binary search bitmasks constructive algorithms dp interactive | Statement | C3 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 4214 | Interactive RBS (Easy Version) | binary search bitmasks constructive algorithms interactive | Statement | C1 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 2857 | Interactive RBS (Medium Version) | binary search bitmasks constructive algorithms interactive | Statement | C2 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 1146 | From the Unknown (Hard Version) | binary search brute force constructive algorithms interactive math | Statement | D2 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1250.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 439 | Grand Finale: Snakes | binary search interactive | Statement | F | Codeforces Round 1058 (Div. 1) {2159} | PROGRAMMING | 3500.0 | Codeforces Round 1058 Editorial | |
| 12788 | Beautiful Permutation | binary search interactive | Statement | D | Codeforces Round 1059 (Div. 3) {2162} | PROGRAMMING | Codeforces Round 1059 (Div. 3) Editorial | ||
| 2803 | Diadrash (Easy Version) | binary search divide and conquer interactive | Statement | D1 | Codeforces Round 1063 (Div. 2) {2163} | PROGRAMMING | 1500.0 | Codeforces Round 1063 Editorial | |
| 1550 | Diadrash (Hard Version) | binary search interactive | Statement | D2 | Codeforces Round 1063 (Div. 2) {2163} | PROGRAMMING | 1250.0 | Codeforces Round 1063 Editorial | |
| 1634 | Locate | binary search constructive algorithms greedy interactive | Statement | B | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 3759 | Flatten or Concatenate | binary search divide and conquer interactive | Statement | E | Good Bye 2025 {2178} | PROGRAMMING | 2250.0 | ||
| 166 | Cacti Classification | binary search interactive math | Statement | C | 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} | PROGRAMMING | Tutorial | ||
| 1353 | Comparable Permutations | binary search greedy interactive sortings two pointers | Statement | C | Codeforces Round 1073 (Div. 1) {2190} | PROGRAMMING | 1750.0 | Codeforces Round 1073 (Div. 1, Div. 2) Editorial | |
| 60 | Bowser's Castle (Easy Version) | binary search constructive algorithms divide and conquer greedy interactive trees | Statement | H1 | Codeforces Round 1085 (Div. 1 + Div. 2) {2207} | PROGRAMMING | 3250.0 | Codeforces Round 1085 (Div. 1 + Div. 2) Editorial | |
| 3721 | Unique Values (Hard version) | binary search constructive algorithms divide and conquer interactive math | Statement | B2 | Codeforces Round 1093 (Div. 1) {2219} | PROGRAMMING | 500.0 | Codeforces Round 1093 (Div. 1, Div. 2) Editorial | |
| 4143 | Unique Values (Easy version) | binary search divide and conquer interactive | Statement | B1 | Codeforces Round 1093 (Div. 1) {2219} | PROGRAMMING | 750.0 | Codeforces Round 1093 (Div. 1, Div. 2) Editorial | |
| 2359 | Seek the Truth | binary search bitmasks interactive | Statement | E | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} | PROGRAMMING | 2250.0 | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial |