Binary Search coding problems

Binary search goes far beyond finding a number in a sorted list: first and last positions, rotated arrays, and searching on the answer itself (minimum capacity, maximum distance). A favourite for medium interview rounds.

25 problems: 12 easy, 10 medium, 3 hard. Free to read; a free account solves them and earns XP and Aura.

1. Count Elements Less Than KPractice · +10 XP · binary search, arrayseasy
2. Count MultiplesPractice · +10 XP · binary search, matheasy
3. Find Duplicate in Sorted ArrayPractice · +10 XP · two pointers, arrays, binary searcheasy
4. Find Element in Sorted ArrayPractice · +10 XP · binary search, arrayseasy
5. Find First Element Greater Than KPractice · +10 XP · two pointers, binary search, sorted arrayeasy
6. Find First OccurrencePractice · +10 XP · binary search, arrays, searchingeasy
7. Find Smallest Missing Positive IntegerPractice · +10 XP · two pointers, binary search, arrayseasy
8. Find Smallest Number Greater Than KPractice · +10 XP · binary search, sorted arrayseasy
9. First Element Greater Than Or Equal To KPractice · +10 XP · binary search, sorted arrays, lower boundeasy
10. Nearest Element in Sorted ArrayPractice · +10 XP · binary search, sorted arrayseasy
11. Square Root Integer PartPractice · +10 XP · binary search, binary search on the answereasy
12. Sum of First N IntegersPractice · +10 XP · binary search, arithmetic serieseasy
13. Maximize Minimum DifferencePractice · +20 XP · binary search, greedymedium
14. Maximum Average SubsegmentPractice · +20 XP · binary search, prefix sums, arraysmedium
15. Maximum Sum of PairsPractice · +20 XP · dynamic programming, prefix sums, binary searchmedium
16. Minimize Maximum DifferencePractice · +20 XP · binary search, greedy, sortingmedium
17. Minimize Maximum Segment SumPractice · +20 XP · binary search, greedymedium
18. Minimum Cost to Make All EqualPractice · +20 XP · binary search, greedymedium
19. Minimum Maximum DifferencePractice · +20 XP · binary search, greedymedium
20. Minimum Maximum Height DifferencePractice · +20 XP · binary search, greedymedium
21. Optimal Apartment RentalPractice · +20 XP · binary search, two pointersmedium
22. Subarray Sum Closest to TargetPractice · +20 XP · prefix sums, binary search, range queriesmedium
23. Longest Non-Decreasing SubsequencePractice · +30 XP · basics, dynamic programming, binary searchhard
24. Minimize Maximum Difference of Grouped ElementsPractice · +30 XP · binary search, greedy, prefix sumshard
25. Minimum Maximum SumPractice · +30 XP · binary search, divide and conquer, greedyhard