Sum of Numbers With Units Digit K

// Accepted solution for LeetCode #2310: Sum of Numbers With Units Digit K
class Solution {
    public int minimumNumbers(int num, int k) {
        if (num == 0) {
            return 0;
        }
        for (int i = 1; i <= num; ++i) {
            int t = num - k * i;
            if (t >= 0 && t % 10 == 0) {
                return i;
            }
        }
        return -1;
    }
}

// Accepted solution for LeetCode #2310: Sum of Numbers With Units Digit K
func minimumNumbers(num int, k int) int {
	if num == 0 {
		return 0
	}
	for i := 1; i <= num; i++ {
		t := num - k*i
		if t >= 0 && t%10 == 0 {
			return i
		}
	}
	return -1
}

# Accepted solution for LeetCode #2310: Sum of Numbers With Units Digit K
class Solution:
    def minimumNumbers(self, num: int, k: int) -> int:
        if num == 0:
            return 0
        for i in range(1, num + 1):
            if (t := num - k * i) >= 0 and t % 10 == 0:
                return i
        return -1

// Accepted solution for LeetCode #2310: Sum of Numbers With Units Digit K
/**
 * [2310] Sum of Numbers With Units Digit K
 *
 * Given two integers num and k, consider a set of positive integers with the following properties:
 *
 * 	The units digit of each integer is k.
 * 	The sum of the integers is num.
 *
 * Return the minimum possible size of such a set, or -1 if no such set exists.
 * Note:
 *
 * 	The set can contain multiple instances of the same integer, and the sum of an empty set is considered 0.
 * 	The units digit of a number is the rightmost digit of the number.
 *
 *  
 * Example 1:
 *
 * Input: num = 58, k = 9
 * Output: 2
 * Explanation:
 * One valid set is [9,49], as the sum is 58 and each integer has a units digit of 9.
 * Another valid set is [19,39].
 * It can be shown that 2 is the minimum possible size of a valid set.
 *
 * Example 2:
 *
 * Input: num = 37, k = 2
 * Output: -1
 * Explanation: It is not possible to obtain a sum of 37 using only integers that have a units digit of 2.
 *
 * Example 3:
 *
 * Input: num = 0, k = 7
 * Output: 0
 * Explanation: The sum of an empty set is considered 0.
 *
 *  
 * Constraints:
 *
 * 	0 <= num <= 3000
 * 	0 <= k <= 9
 *
 */
pub struct Solution {}

// problem: https://leetcode.com/problems/sum-of-numbers-with-units-digit-k/
// discuss: https://leetcode.com/problems/sum-of-numbers-with-units-digit-k/discuss/?currentPage=1&orderBy=most_votes&query=

// submission codes start here

impl Solution {
    pub fn minimum_numbers(num: i32, k: i32) -> i32 {
        0
    }
}

// submission codes end

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    #[ignore]
    fn test_2310_example_1() {
        let num = 58;
        let k = 9;

        let result = 2;

        assert_eq!(Solution::minimum_numbers(num, k), result);
    }

    #[test]
    #[ignore]
    fn test_2310_example_2() {
        let num = 37;
        let k = 2;

        let result = -1;

        assert_eq!(Solution::minimum_numbers(num, k), result);
    }

    #[test]
    #[ignore]
    fn test_2310_example_3() {
        let num = 0;
        let k = 7;

        let result = 0;

        assert_eq!(Solution::minimum_numbers(num, k), result);
    }
}

// Accepted solution for LeetCode #2310: Sum of Numbers With Units Digit K
function minimumNumbers(num: number, k: number): number {
    if (!num) return 0;
    let digit = num % 10;
    for (let i = 1; i < 11; i++) {
        let target = i * k;
        if (target <= num && target % 10 == digit) return i;
    }
    return -1;
}