1-oxygen-levels.js

/*
Many years into the future, a team of Space Voyagers find their ship is low on Oxygen and need to dock
somewhere safe while they call home for help.
  
Their computer detects a list of nearby planets that have Oxygen in their atmosphere. It has produced an array of their Oxygen levels.

To be safe to land on, a planet needs to have an Oxygen level between 19.5% and 23.5%.

Write a function that finds the first safe oxygen level in the array - Oxygen between 19.5% and 23.5%
*/

function safeLevels(levels) {
    return levels.find(level => {
        let levelNum = parseFloat(level)
        return (levelNum > 19.5) && (levelNum < 23.5)
    })

}

/* ======= TESTS - DO NOT MODIFY ===== */

const oxygenLevels1 = ["24.2%", "11.3%", "19.9%", "23.1%", "29.3%", "20.2%"];
const oxygenLevels2 = ["30.8%", "23.5%", "18.8%", "19.5%", "20.2%", "31.6%"];
const oxygenLevels3 = ["200%", "21.1%"];

const util = require('util');

function test(test_name, actual, expected) {
    let status;
    if (actual === expected) {
        status = "PASSED";
    } else {
        status = `FAILED: expected: ${util.inspect(expected)} but your function returned: ${util.inspect(actual)}`;
    }

    console.log(`${test_name}: ${status}`);
}

test(
    "safeLevels function works - case 1",
    safeLevels(oxygenLevels1),
    "19.9%"
);

test(
    "safeLevels function works - case 2",
    safeLevels(oxygenLevels2),
    "20.2%"
);

test(
    "safeLevels function works - case 3",
    safeLevels(oxygenLevels3),
    "21.1%"
);