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// Time Complexity : O(N)// Space Complexity : O(1)var isMonotonic = function(nums) {let isMono = null;for(let i = 1; i < nums.length; i++) {if(isMono === null) {if(nums[i - 1] < nums[i]) isMono = 0;else if(nums[i - 1] > nums[i]) isMono = 1;continue;}if(nums[i - 1] < nums[i] && isMono !== 0) {return false;}else if(nums[i - 1] > nums[i] && isMono !== 1) {return false;}}return true;};let nums1 = [1,2,2,3]let nums2 = [6,5,4,4]let nums3 = [1,3,2]console.log(isMonotonic(nums1));console.log(isMonotonic(nums2));console.log(isMonotonic(nums3));
const kNearestNeighbors = (data, labels, point, k = 3) => {const kNearest = data.map((el, i) => ({dist: Math.hypot(...Object.keys(el).map(key => point[key] - el[key])),label: labels[i]})).sort((a, b) => a.dist - b.dist).slice(0, k);return kNearest.reduce((acc, { label }, i) => {acc.classCounts[label] =Object.keys(acc.classCounts).indexOf(label) !== -1? acc.classCounts[label] + 1: 1;if (acc.classCounts[label] > acc.topClassCount) {acc.topClassCount = acc.classCounts[label];acc.topClass = label;}return acc;},{classCounts: {},topClass: kNearest[0].label,topClassCount: 0}).topClass;};const data = [[0, 0], [0, 1], [1, 3], [2, 0]];const labels = [0, 1, 1, 0];kNearestNeighbors(data, labels, [1, 2], 2); // 1kNearestNeighbors(data, labels, [1, 0], 2); // 0
function sortNumbers(arr) {return arr.slice().sort((a, b) => a - b);}const unsortedArray = [4, 1, 9, 6, 3, 5];const sortedArray = sortNumbers(unsortedArray);console.log("Unsorted Numbers:", unsortedArray);console.log("\n");console.log("Sorted Numbers:", sortedArray);
const geometricProgression = (end, start = 1, step = 2) =>Array.from({length: Math.floor(Math.log(end / start) / Math.log(step)) + 1,}).map((_, i) => start * step ** i);geometricProgression(256); // [1, 2, 4, 8, 16, 32, 64, 128, 256]geometricProgression(256, 3); // [3, 6, 12, 24, 48, 96, 192]geometricProgression(256, 1, 4); // [1, 4, 16, 64, 256]
console.log("hello world")
const head = arr => (arr && arr.length ? arr[0] : undefined);head([1, 2, 3]); // 1head([]); // undefinedhead(null); // undefinedhead(undefined); // undefined