Beginner
1. Arithmetic Progression2. Geometric Progression3. Harmonic Progression4. No of triangles 5. Area of Polygon6. Trailing Zeros7. Min Platforms 8. Trapping Rain 9. Jump numbers10. Segregation of 0’s and 1’s11. Two SUM12. Triplet sum 13. Diagonal Sum14. Addition of two matrixes15. Subtraction of two matrixes16. Multiplication of two matrixes17. Transpose of given array18. Spiral Matrix19. Most Frequent Element20. Majority Element 21. Max difference 22. Odd occurring23. Second Largest and Second Smallest24. Next greater number25. Count Unique Elements26. Common elements 27. Removing Duplicates28. Balanced Array29. Rotating Array by k times30. Reverse Array31. Wave Array32. Merge arrays 33. Constraint Sort34. Find element in Sorted rotated array35. Sub Array Sum36. Largest subarray of 0’s and 1’s 37. K-Sub Array38. Max subarray sum39. Contiguous Square SumCount Unique Elements
LEVEL:Beginner
Description
Given list of elements. You have to find the number of unique elements in a given list.
Input Format
First line contains a number N. Next line contains N integers separated by spaces.
Output Format
Print number of unique elements present.
5 3 5 4 4 1
4
8 2 5 4 3 4 1 2 7
6
10 9 3 8 4 7 5 9 2 3 8
7
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Approach
Approach 1: Using Brute Force
Step-i) Initialize count to 0
Step-ii) check whether the current character as repeated in the string or not using loop
Step-iii) if it is repeated increment the count
Step-iv) Repeat ii and iii till all the characters of checked
Step-v) return count
Time Complexity: O(n^2)
Space Complexity: O(n)
Approach 2: Using set
Step-i)Create a empty set
Step-ii) Traverse the array and add elements to the set
Step-iii) Repeat the step ii till complete array is traversed
Step-iv) Find the size of the set
Step-v) Return the size of the set
Time Complexity: O(n)
Space Complexity: O(n)
Note :
Let us know if you can come up with a better approach, mail us at support@theinquisitive.in Your approach will be reviewed and posted with credits to you.
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