odeling the spread of a virus like COVID-19 using recursion. Let N = total population (assumed constant, disregarding deaths, births, immigration, and emigration). S n = number who are susceptible to the disease at time n (n is in weeks). I n = number who are infected (and contagious) at time n.

You are given a N*N maze with a rat placed at maze[0][0]. Find whether any path exist that rat can follow to reach its destination i.e. maze[N-1][N-1]. Rat can move in any direc­tion ( left, right, up and down).Value of every cell in the maze can either be 0 or 1. Cells with value 0 are blocked means rat can­not enter into those cells and those with value 1 are open.Input FormatLine 1: Integer NNext N Lines: Each line will contain ith row elements (separated by space)Output Format :The output line contains true if any path exists for the rat to reach its destination otherwise print false.Sample Input 1 :31 0 11 0 11 1 1Sample Output 1 :trueSample Input 2 :31 0 11 0 10 1 1Sample Output 2 : false Solution: //// public class Solution {     public static boolean ratInAMaze(int maze[][]){         int n = maze.length;        int path[][] = new int[n][n];         return solveMaze(maze, 0, 0, path);    }       public static boolean solveMaze(int[][] maze, int i, int j, int[][] path) {//…

Write in java

Give a recursive definition for the set of all strings of a’s and b’s that begins with an a and ends in a b. Say, S = { ab, aab, abb, aaab, aabb, abbb, abab..} Let S be the set of all strings of a’s and b’s that begins with a and ends in a b. The recursive definition is as follows – Base:... Recursion: If u ∈ S, then... Restriction: There are no elements of S other than those obtained from the base and recursion of S.

A set SS of strings of characters is defined recursively by aa and bb belong to SS . If xx belongs to SS , so does xbxb . Which one of the  following strings belong to SS ? this is the Group of answer choices 1. aba 2. bbbbb 3. ab 4. aaab 5. a

Computer Science 1. Let Σ = {0, 1} be an alphabet.(a) Let w = 101 be a word over Σ. Compute |w|, the length of w.(b) List all of the words in Σ32. Let {a, b, c} be an alphabet. List all of the words in Σ23. Let Σ = {a, b} be an alphabet and let · denote concatenation. Compute (ba · ε) · abb,where ε is the empty word.4. Let Σ = {0, 1} be an alphabet and let L ⊆ {0, 1} ∗ be the language defined as L = {w ∈ {0, 1} ∗ |w = x10y, x, y ∈ {0, 1}∗}. (a) Determine whether 01 ∈ L.(b) Determine whether 0101 ∈ L. 5. Let Σ = {0, 1} be an alphabet and let L ⊆ Σ ∗ be the language consisting of all wordsover Σ that contain the substring 10. Construct a DFA that accepts L.   Thank you in advance

Using Dr Racket, write a tail recursive function called popadd that models a population with P people at time t = 0 and adds d people per year

@1st mp. 109.

Q.  Given a 2d grid map of '1's (land) and '0's (water),count the number of islands.An island is surrounded by water and is formed byconnecting adjacent lands horizontally or vertically.You may assume all four edges of the grid are all surrounded by water. Example 1: 11110110101100000000Answer: 1 Example 2: 11000110000010000011Answer: 3""" def num_islands(grid):    count = 0    for i in range(len(grid)):        for j, col in enumerate(grid[i]):            if col == 1:                dfs(grid, i, j)                count += 1 Please code it. .

Imagine there are N teams competing in a tournament, and that each team plays each of the other teams once. If a tournament were to take place, it should be demonstrated (using an example) that every team would lose to at least one other team in the tournament.