Software Engineer

You are given a list of rectangles where each rectangle is represented by an array of four integers (i.e. Rectangle[i]=[x1, y1, x2, y2], where x1, y1 represents the bottom left point of the rectangle and x2.y2 represents the top right point of the rectangle, you have to find the total area covered by all the rectangles in the plane.

Example :

Rectangles = [[0, 0, 2, 2], [1, 0, 2, 3],[1, 0, 3, 1]], 

For the given three rectangles, you can observe that the first rectangle occupies an area of 4 units and the second rectangle has an area of 3 units, but we have to keep one thing also in mind that they have an area of 3 units common overlapping among them, so we cannot include it again, so the final area which comes out for all the rectangles is 6 units.

Total Area = 6 units

You are given a sequence of only digits in the form of a string 'DIGIT_PATTERN', your task is to find the first repeating digit. If no digit is repeating you should return -1.

Example:

Given string of digits is 123456325. Now starting from the left, the first digit which is repeating is 3 as till 2nd 3 every digit is encountered 1st time and thus our answer for this input will be 3.

Given an input string (STR), print all possible permutations of the input string.

Note:

The input string may contain the same characters, so there will also be the same permutations.
The order of permutations doesn’t matter.