| 2 | Add Two Numbersread | — | Medium | Linked ListMathRecursion | 46% | |
| 7 | Reverse Integer | — | Medium | Math | 30% | |
| 9 | Palindrome Number | — | Easy | Math | 59% | |
| 12 | Integer to Roman | — | Medium | Hash TableMathString | 68% | |
| 13 | Roman to Integerread | — | Easy | Hash TableMathString | 65% | |
| 29 | Divide Two Integersread | — | Medium | MathBit Manipulation | 18% | |
| 43 | Multiply Stringsread | — | Medium | MathStringSimulation | 42% | |
| 48 | Rotate Image | — | Medium | ArrayMathMatrix | 78% | |
| 50 | Pow(x, n) | — | Medium | MathRecursion | 37% | |
| 60 | Permutation Sequence | — | Hard | MathRecursion | 50% | |
| 62 | Unique Paths | — | Medium | MathDynamic ProgrammingCombinatorics | 66% | |
| 66 | Plus One | — | Easy | ArrayMath | 47% | |
| 67 | Add Binary | — | Easy | MathStringBit Manipulation | 56% | |
| 69 | Sqrt(x) | — | Easy | MathBinary Search | 40% | |
| 70 | Climbing Stairs | — | Easy | MathDynamic ProgrammingMemoization | 53% | |
| 89 | Gray Code | — | Medium | MathBacktrackingBit Manipulation | 62% | |
| 96 | Unique Binary Search Trees | — | Medium | MathDynamic ProgrammingTree | 62% | |
| 149 | Max Points on a Line | — | Hard | ArrayHash TableMath | 29% | |
| 150 | Evaluate Reverse Polish Notationread | — | Medium | ArrayMathStack | 55% | |
| 166 | Fraction to Recurring Decimal | — | Medium | Hash TableMathString | 26% | |
| 168 | Excel Sheet Column Title | — | Easy | MathString | 43% | |
| 171 | Excel Sheet Column Number | — | Easy | MathString | 66% | |
| 172 | Factorial Trailing Zeroes | — | Medium | Math | 45% | |
| 189 | Rotate Array | — | Medium | ArrayMathTwo Pointers | 43% | |
| 202 | Happy Number | — | Easy | Hash TableMathTwo Pointers | 58% | |
| 204 | Count Primes | — | Medium | ArrayMathEnumeration | 35% | |
| 223 | Rectangle Area | — | Medium | MathGeometry | 47% | |
| 224 | Basic Calculator | — | Hard | MathStringStack | 45% | |
| 227 | Basic Calculator II | — | Medium | MathStringStack | 46% | |
| 231 | Power of Two | — | Easy | MathBit ManipulationRecursion | 48% | |
| 233 | Number of Digit One | — | Hard | MathDynamic ProgrammingRecursion | 36% | |
| 241 | Different Ways to Add Parenthesesread | — | Medium | MathStringDynamic Programming | 72% | |
| 258 | Add Digits | — | Easy | MathSimulationNumber Theory | 68% | |
| 263 | Ugly Number | — | Easy | Math | 42% | |
| 264 | Ugly Number II | — | Medium | Hash TableMathDynamic Programming | 49% | |
| 268 | Missing Number | — | Easy | ArrayHash TableMath | 70% | |
| 273 | Integer to English Words | — | Hard | MathStringRecursion | 34% | |
| 279 | Perfect Squares | — | Medium | MathDynamic ProgrammingBreadth-First Search | 56% | |
| 282 | Expression Add Operators | — | Hard | MathStringBacktracking | 41% | |
| 292 | Nim Game | — | Easy | MathBrainteaserGame Theory | 58% | |
| 313 | Super Ugly Number | — | Medium | ArrayMathDynamic Programming | 45% | |
| 319 | Bulb Switcherread | — | Medium | MathBrainteaser | 54% | |
| 326 | Power of Three | — | Easy | MathRecursion | 48% | |
| 335 | Self Crossing | — | Hard | ArrayMathGeometry | 32% | |
| 342 | Power of Four | — | Easy | MathBit ManipulationRecursion | 49% | |
| 343 | Integer Break | — | Medium | MathDynamic Programming | 61% | |
| 365 | Water and Jug Problem | — | Medium | MathDepth-First SearchBreadth-First Search | 43% | |
| 367 | Valid Perfect Square | — | Easy | MathBinary Search | 44% | |
| 368 | Largest Divisible Subset | — | Medium | ArrayMathDynamic Programming | 49% | |
| 371 | Sum of Two Integers | — | Medium | MathBit Manipulation | 54% | |