2310-Sum-of-Numbers-With-Units-Digit-K.java

//Contest 298 problem brute-force. Feel free to update this.
class Solution {
    public int minimumNumbers(int num, int k) {
        if (num == 0) return 0;
        if (num%10 == k) return 1;
        if (k == 0 && num%10 == 0) return 1;
        else if (k==0 && num%10!=0) return -1;
        int temp = num;
        num -= k;
        int len = 1;
        while (num>0) {
            len++;
            if (num%10 == k) return len;
            num -= k;
        }
        return num<0?-1:len;
    }
}