Category: hacker rank

Algorithms/Data Structures — [Problem Solving] 

An Institutional Broker wants to Review their Book of Customers to see which are Most Active. Given a List of Trades By "Customer Name, Determine which Customers Account for At Least 5% of the Total Number of Trades. Order the List Alphabetically Ascending By Name."

Example
n = 23
"customers = {"Bigcorp", "Bigcorp", "Acme", "Bigcorp", "Zork", "Zork", "Abe", "Bigcorp", "Acme", "Bigcorp", "Bigcorp", "Zork", "Bigcorp", "Zork", "Zork", "Bigcorp", "Acme", "Bigcorp", "Acme", "Bigcorp", "Acme", "Littlecorp", "Nadircorp"}."

"Bigcorp had 10 Trades out of 23, which is 43.48% of the Total Trades."
"Both Acme and Zork had 5 trades, which is 21.74% of the Total Trades."
"The Littlecorp, Nadircorp, and Abe had 1 Trade Each, which is 4.35%..."

Algorithms/Data Structures — [Problem Solving] 

There is a Specific Need for Changes in a List of Usernames. In a given List of Usernames — For Each Username — If the Username can be Modified and Moved Ahead in a Dictionary. The Allowed Modification is that Alphabets can change Positions in the Given Username.

Example

usernames[] = {"Aba", "Cat"}

 

"Aba" can be Changed to only "Baa" — Hence, It can Never Find a Place Ahead in the Dictionary. Hence, Output will be "NO". "Cat" can be Changed to "Act", "Atc", "Tca", "Tac", "Cta" and Definitely "Act" will Find a Place Before "Cat" in the Dictionary. Hence, Output will be "YES".

[Function Description]
Complete the function possibleChanges in the Editor Below.
 

possibleChanges has the Following Parameters:
String usernames[n]: An Array of User Names
 

Returns String[n]: An Array with "YES" or "NO" Based on Feasibility
(Actual Question Says String Array, But Signature is List of Strings)

Constraints
• [No Special Constraints Exist, But Cannot Recall Exactly]

Input Format 
"The First Line Contains an Integer, n, the Number of Elements in Usernames.",

"Each Line of the n Subsequent Lines (where 0 < i < n) contains a String usernames[i]."        

[Sample Case 0 — Sample Input For Custom Testing]         
5
Aba

Cat

Boby

Buba

Bapg

Sungi

Lapg

Acba

       

Sample Output (Each Should Be on a Separate Line) 

NO YES NO YES YES YES YES YES

   

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[Explanation of the Solution]
This is again a Good Question from Hacker Rank to Test Your Logic / Problem Solving Abilities. The Core Point to Handle is that For Each Combination of 2 Alphabets that Exists in the Username String > We Need to Check if the Latter Occurring Character (ASCII) is Less than the Former Occurring Character (ASCII). For Example in the String "Bapg" — For a Selection of "Ba" from "Bapg" — We have "a" Occurring Before "B" in the English Alphabet. We can Have Two Loops (One Nested) to Decide for a Combination of Each Two Alphabets. The Time Complexity of this Solution is O(n^2).

 

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[Source Code, Sumith Puri (c) 2021 — Free to Use and Distribute]