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Problem Statement

Multiverse wants to enhance their Mars Rover system with the following capabilities:

Part 1: Obstacle Detection

The Mars surface has obstacles that rovers must navigate around. Extend the system to detect collisions with obstacles: when a rover tries to move into an obstacle, it should stop at its current position (not move forward) but continue processing remaining commands.

Note the updated input format: obstacles may be specified in the grid object.

New Input Format:

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Write a function using the React JavaScript framework to navigate a trireme using the stars.

import React, { useState } from 'react';

// Example star directions
const STAR_DIRECTIONS = [
  { name: 'North Star (Polaris)', heading: 'North' },

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class Solution:
    def exist(self, board: List[List[str]], word: str) -> bool:
        for x in range(len(board[0])):
            for y in range(len(board)):
                # doing the equality check here means that we omit one layer of
                # recursive function calls, which speeds things up considerably
                if board[y][x] == word[0] and self.__continuesFrom(board, word, 0, x, y):
                    return True
        return False

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Mars Rover

Write a program that takes in commands and moves one or more robots around Mars.

• The world should be modelled as a grid with size m x n
• Your program should read the input, update the robots, and print out the final states of the robots
• Each robot has a position (x, y), and an orientation (N, E, S, W)
• Each robot can move forward one space (F), rotate left by 90 degrees (L), or rotate

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If I add a boolean auto_onboard_via_dpt column to the cohort_companies table, how can I ensure that at most one row has a true value for this column for a given company id?

To ensure that at most one row in the cohort_companies table has auto_onboard_via_dpt = true for a given company_id, you want to enforce a partial unique index (sometimes called a filtered unique index) at the database level.

Assuming you are using PostgreSQL (the most common DB for Elixir/Phoenix projects), you can do this with the following SQL:

CREATE UNIQUE INDEX unique_auto_onboard_via_dpt_per_company
ON cohort_companies (company_id)
WHERE auto_onboard_via_dpt IS TRUE;

addrummond

Problem Statement

Multiverse wants to enhance their Mars Rover system with the following capabilities:

Part 1: Obstacle Detection

The Mars surface has obstacles that rovers must navigate around. Extend the system to:

1. Add obstacle support: Modify the grid to include obstacle positions
2. Collision detection: When a rover tries to move into an obstacle, it should stop at its current position (not move forward) but continue processing remaining commands
3. Update input format: Obstacles should be specified after the grid dimensions

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succeed

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fail

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defmodule HtmlLintNative do
  use Rustler, otp_app: :platform, crate: "platform_plugs_htmllintnative"
 
  def add(_a, _b), do: error()
 
  def lint(_html_string), do: error()
 
  defp error(), do: :erlang.nif_error(:nif_not_loaded)
end

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#[rustler::nif]
fn lint(env: Env, input: String) -> Result<Term, Error> {
    let parse_errors = lint_html::lint(input);
    return convert_errors(env, parse_errors);
}

fn convert_errors(env: Env, parse_errors: Vec<(u64, String)>) -> Result<Term, Error> {
    if parse_errors.len() == 0 {
        return Ok(ok().to_term(env));
    } else {