Enumerate All Possible Decimal Strings Length n

Enumerate all possible decimal strings of length n.

DFS Recursive divide-and-conquer

/*
Time Complexity - O(n * 10^n)
Space Complexity - O(n). Height of tree or length of prefix of partial slate which increases with depth.
*/

function decimalStrings(n) {
	if (n < 1) return []

	const result = []
	dsHelper('', n)
	return result

	function dsHelper(slate, n) {
		if (n === 0) result.push(slate)
		else {
			for (let i = 0; i < 10; i++) {
				dsHelper(slate + `${i}`, n - 1)
			}
		}
	}
}

Tests:

// Tests
const tests = [
	[1, ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']],
	[0, []],
	[
		2,
		[
			'00',
			'01',
			'02',
			'03',
			'04',
			'05',
			'06',
			'07',
			'08',
			'09',
			'10',
			'11',
			'12',
			'13',
			'14',
			'15',
			'16',
			'17',
			'18',
			'19',
			'20',
			'21',
			'22',
			'23',
			'24',
			'25',
			'26',
			'27',
			'28',
			'29',
			'30',
			'31',
			'32',
			'33',
			'34',
			'35',
			'36',
			'37',
			'38',
			'39',
			'40',
			'41',
			'42',
			'43',
			'44',
			'45',
			'46',
			'47',
			'48',
			'49',
			'50',
			'51',
			'52',
			'53',
			'54',
			'55',
			'56',
			'57',
			'58',
			'59',
			'60',
			'61',
			'62',
			'63',
			'64',
			'65',
			'66',
			'67',
			'68',
			'69',
			'70',
			'71',
			'72',
			'73',
			'74',
			'75',
			'76',
			'77',
			'78',
			'79',
			'80',
			'81',
			'82',
			'83',
			'84',
			'85',
			'86',
			'87',
			'88',
			'89',
			'90',
			'91',
			'92',
			'93',
			'94',
			'95',
			'96',
			'97',
			'98',
			'99',
		],
	],
]

console.log('Recursive divide-and-conquer')
for (const test of tests) {
	const res = decimalStrings(test[0])
	console.log(res)
	console.log(JSON.stringify(res) === JSON.stringify(test[1]))
}