2310. Sum of Numbers With Units Digit K
Description
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
Solutions
Solution 1
1 2 3 4 5 6 7 8 |
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
|
1 2 3 4 5 6 7 8 9 10 11 |
|
1 2 3 4 5 6 7 8 9 10 11 12 |
|
1 2 3 4 5 6 7 8 9 |
|
Solution 2
1 2 3 4 5 6 7 8 |
|
1 2 3 4 5 6 7 8 9 10 11 12 13 |
|