| 3138 | Minimum Length of Anagram Concatenation | Hash TableStringCounting | Medium |
| 3139 | Minimum Cost to Equalize Array | ArrayGreedyEnumeration | Hard |
| 3142 | Check if Grid Satisfies Conditions | ArrayMatrix | Easy |
| 3143 | Maximum Points Inside the Square | ArrayHash TableString+2 | Medium |
| 3144 | Minimum Substring Partition of Equal Character Frequency | Hash TableStringDynamic Programming+1 | Medium |
| 3145 | Find Products of Elements of Big Array | ArrayBinary SearchBit Manipulation | Hard |
| 3146 | Permutation Difference between Two Strings | Hash TableString | Easy |
| 3147 | Taking Maximum Energy From the Mystic Dungeon | ArrayPrefix Sum | Medium |
| 3148 | Maximum Difference Score in a Grid | ArrayDynamic ProgrammingMatrix | Medium |
| 3149 | Find the Minimum Cost Array Permutation | ArrayDynamic ProgrammingBit Manipulation+1 | Hard |
| 3151 | Special Array I | Array | Easy |
| 3152 | Special Array II | ArrayBinary SearchPrefix Sum | Medium |
| 3153 | Sum of Digit Differences of All Pairs | ArrayHash TableMath+1 | Medium |
| 3154 | Find Number of Ways to Reach the K-th Stair | MathDynamic ProgrammingBit Manipulation+2 | Hard |
| 3158 | Find the XOR of Numbers Which Appear Twice | ArrayHash TableBit Manipulation | Easy |
| 3159 | Find Occurrences of an Element in an Array | ArrayHash Table | Medium |
| 3160 | Find the Number of Distinct Colors Among the Balls | ArrayHash TableSimulation | Medium |
| 3161 | Block Placement Queries | ArrayBinary SearchBinary Indexed Tree+1 | Hard |
| 3162 | Find the Number of Good Pairs I | ArrayHash Table | Easy |
| 3163 | String Compression III | String | Medium |
| 3164 | Find the Number of Good Pairs II | ArrayHash Table | Medium |
| 3165 | Maximum Sum of Subsequence With Non-adjacent Elements | ArrayDivide and ConquerDynamic Programming+1 | Hard |
| 3168 | Minimum Number of Chairs in a Waiting Room | StringSimulation | Easy |
| 3169 | Count Days Without Meetings | ArraySorting | Medium |
| 3170 | Lexicographically Minimum String After Removing Stars | Hash TableStringStack+2 | Medium |
| 3171 | Find Subarray With Bitwise OR Closest to K | ArrayBinary SearchBit Manipulation+1 | Hard |
| 3174 | Clear Digits | StringStackSimulation | Easy |
| 3175 | Find The First Player to win K Games in a Row | ArraySimulation | Medium |
| 3176 | Find the Maximum Length of a Good Subsequence I | ArrayHash TableDynamic Programming | Medium |
| 3177 | Find the Maximum Length of a Good Subsequence II | ArrayHash TableDynamic Programming | Hard |
| 3178 | Find the Child Who Has the Ball After K Seconds | MathSimulation | Easy |
| 3179 | Find the N-th Value After K Seconds | ArrayMathSimulation+2 | Medium |
| 3180 | Maximum Total Reward Using Operations I | ArrayDynamic Programming | Medium |
| 3181 | Maximum Total Reward Using Operations II | ArrayDynamic ProgrammingBit Manipulation | Hard |
| 3184 | Count Pairs That Form a Complete Day I | ArrayHash TableCounting | Easy |
| 3185 | Count Pairs That Form a Complete Day II | ArrayHash TableCounting | Medium |
| 3186 | Maximum Total Damage With Spell Casting | ArrayHash TableTwo Pointers+4 | Medium |
| 3187 | Peaks in Array | ArrayBinary Indexed TreeSegment Tree | Hard |
| 3190 | Find Minimum Operations to Make All Elements Divisible by Three | ArrayMath | Easy |
| 3191 | Minimum Operations to Make Binary Array Elements Equal to One I | ArrayBit ManipulationQueue+2 | Medium |
| 3192 | Minimum Operations to Make Binary Array Elements Equal to One II | ArrayDynamic ProgrammingGreedy | Medium |
| 3193 | Count the Number of Inversions | ArrayDynamic Programming | Hard |
| 3194 | Minimum Average of Smallest and Largest Elements | ArrayTwo PointersSorting | Easy |
| 3195 | Find the Minimum Area to Cover All Ones I | ArrayMatrix | Medium |
| 3196 | Maximize Total Cost of Alternating Subarrays | ArrayDynamic Programming | Medium |
| 3197 | Find the Minimum Area to Cover All Ones II | ArrayMatrixEnumeration | Hard |
| 3200 | Maximum Height of a Triangle | ArrayEnumeration | Easy |
| 3201 | Find the Maximum Length of Valid Subsequence I | ArrayDynamic Programming | Medium |
| 3202 | Find the Maximum Length of Valid Subsequence II | ArrayDynamic Programming | Medium |
| 3203 | Find Minimum Diameter After Merging Two Trees | TreeDepth-First SearchBreadth-First Search+1 | Hard |