Machine learning engineer

Given a string S containing digits from 2 to 9 inclusive. Your task is to find all possible letter combinations that the number could represent.

A mapping from Digits to Letters (just like in Nokia 1100) is shown below. Note that 1 does not map to any letter.

You are given a sorted array 'arr' of distinct values and a target value 'm'. You need to search for the index of the target value in the array.

Note:

1. If the value is present in the array, return its index.
2. If the value is absent, determine the index where it would be inserted in the array while maintaining the sorted order. 
3. The given array has distinct integers.
4. The given array may be empty.

Example:

Input:  arr = [1, 2, 4, 7],  m = 6 

Output: 3

Explanation: If the given array 'arr' is: [1, 2, 4, 7] and m = 6. We insert m = 6 in the array and get 'arr' as: [1, 2, 4, 6, 7]. The position of 6 is 3 (according to 0-based indexing)

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You are given a string 's' that represents a Roman number. Convert the Roman number to an integer and return it.

Roman numerals are represented by seven different symbols: I, V, X, L, C, D, and M.

Table of values:

Symbol       Value
I             1
V             5
X             10
L             50
C             100
D             500
M             1000

For example:

3 is written as III in Roman numeral, just three ones added together. 13 is written as XIII, which is simply X + III. The number 25 is written as XXV, which is XX + V 

You have been given an array/list of strings 'inputStr'. You are supposed to return the strings as groups of anagrams such that strings belonging to a particular group are anagrams of one another.

An anagram is a word or phrase formed by rearranging the letters of a different word or phrase. We can generalize this in string processing by saying that an anagram of a string is another string with the same quantity of each character in it, in any order.

Note:

The order in which the groups and members of the groups are printed does not matter.

For example:

inputStr = {"eat","tea","tan","ate","nat","bat"}
Here {“tea”, “ate”,” eat”} and {“nat”, “tan”} are grouped as anagrams. Since there is no such string in “inputStr” which can be an anagram of “bat”, thus, “bat” will be the only member in its group.

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