Software Engineer

You are given a string 'STR'. The string contains [a-z] [A-Z] [0-9] [special characters]. You have to find the reverse of the string.

For example:

 If the given string is: STR = "abcde". You have to print the string "edcba".

follow up:

Try to solve the problem in O(1) space complexity. 

You are given a string 'STR' consisting of lowercase English letters. Your task is to return all permutations of the given string in lexicographically increasing order.

String A is lexicographically less than string B, if either A is a prefix of B (and A ≠ B), or there exists such i (1 <= i <= min(|A|, |B|)), that A[i] < B[i], and for any j (1 <= j < i) A[i] = B[i]. Here |A| denotes the length of the string A.

For example :

If the string is “bca”, then its permutations in lexicographically increasing order are { “abc”, “acb”, “bac”, “bca”, “cab”, “cba” }.

Note:

Given string contains unique characters.

Implement a Calculator using Class and OOPs Concepts.

Given a string 'S' of length 'L', return the length of the longest substring without repeating characters.

Example:

Suppose given input is "abacb", then the length of the longest substring without repeating characters will be 3 ("acb").

Given a 2D matrix 'A' of size 'M' x 'N' containing only integers 0, 1, and 2.

Each 2 represents a rotten tomato, each 1 represents a fresh tomato, and each 0 represents an empty cell. A rotten tomato at position (i, j) can rot any adjacent fresh tomato at (i-1, j), (i+1, j), (i, j-1), or (i, j+1) in one unit of time.

Find the minimum time required for all fresh tomatoes to become rotten. If it's impossible for all fresh tomatoes to rot, return -1.

For Example :

Let 'M' = 3, 'N' = 3, and 'A' =
2 1 1
1 1 0
0 1 1

Initially, the rotten tomato is at (0, 0).
After 1 minute, the fresh tomatoes at (0, 1) and (1, 0) become rotten.
The matrix becomes:
2 2 1
2 1 0
0 1 1

After 2 minutes, the tomato at (1, 1) becomes rotten (from (0,1) or (1,0)).
The matrix becomes:
2 2 1
2 2 0
0 1 1

After 3 minutes, the tomatoes at (0, 2) and (2, 1) become rotten.
The matrix becomes:
2 2 2
2 2 0
0 2 1

After 4 minutes, the tomato at (2, 2) becomes rotten.
The matrix becomes:
2 2 2
2 2 0
0 2 2
All fresh tomatoes have become rotten. The minimum time taken is 4.

You have been given a permutation of ‘N’ integers. A sequence of ‘N’ integers is called a permutation if it contains all integers from 1 to ‘N’ exactly once. Your task is to rearrange the numbers and generate the lexicographically next greater permutation.

To determine which of the two permutations is lexicographically smaller, we compare their first elements of both permutations. If they are equal — compare the second, and so on. If we have two permutations X and Y, then X is lexicographically smaller if X[i] < Y[i], where ‘i’ is the first index in which the permutations X and Y differ.

For example, [2, 1, 3, 4] is lexicographically smaller than [2, 1, 4, 3].