SDE - 1

You have been given an array/list 'ARR' of integers. Your task is to find the second largest element present in the 'ARR'.

Note:

a) Duplicate elements may be present.

b) If no such element is present return -1.

Example:

Input: Given a sequence of five numbers 2, 4, 5, 6, 8.

Output:  6

Explanation:
In the given sequence of numbers, number 8 is the largest element, followed by number 6 which is the second-largest element. Hence we return number 6 which is the second-largest element in the sequence.

You have been given two strings ‘STR1’ and ‘STR2’.

Your task is to find if ‘STR1’ is a subsequence of ‘STR2’.

A subsequence of a string is a new string that can be derived from the original string by deleting some characters (can be none) without changing the relative ordering of other characters.

Example:

‘ACE’ is a subsequence of ‘ABCDE’ because ‘ACE’ can be formed by deleting ‘B’ and ‘D’ without changing the relative order of characters. ‘ADB’ is not a subsequence of ‘ABCDE’ because we can get ‘ABD’ from ‘ABCDE’ but not ‘ADB’ and in ‘ADB’ relative order of ‘B’ and ‘D’ are different from original strings.

Note:

1.Strings ‘STR1’ and ‘STR2’ consists only of English uppercases.

2.Length of string ‘STR2’ will always be greater than or equal to the length of string ‘STR1’.

Example:

For example, the given ‘STR1’ is ‘BAE’ and ‘STR2’ is ‘ABADE’. 
String ‘STR1’ is a subsequence of string ‘STR2’ because ‘BAE’ can be formed by deleting ‘A’ and ‘D’ from ‘ABADE’ and the relative ordering of the characters of the string ‘ABADE’ persists.

You are given a sorted integer array 'arr' of size 'n'.

You need to remove the duplicates from the array such that each element appears only once.

Return the length of this new array.

Note:

Do not allocate extra space for another array. You need to do this by modifying the given input array in place with O(1) extra memory. 

For example:

'n' = 5, 'arr' = [1 2 2 2 3].
The new array will be [1 2 3].
So our answer is 3.

You have been given an integer array/list(ARR) of size 'N'. It only contains 0s, 1s and 2s. Write a solution to sort this array/list.

Note :

Try to solve the problem in 'Single Scan'. ' Single Scan' refers to iterating over the array/list just once or to put it in other words, you will be visiting each element in the array/list just once.

How to measure a length of a rope using two candles

You are given an array “ARR” of size N. Your task is to find out the sum of maximum and minimum elements in the array.

Follow Up:

Can you do the above task in a minimum number of comparisons?