#2522
Partition String Into Substrings With Values at Most K
medium · verified · 47.5% accepted · 393 likes · top 32%
string · dynamic programming · greedy
Description
You are given a string s consisting of digits from 1 to 9 and an integer k.
A partition of a string s is called good if:
- Each digit of s is part of exactly one substring.
- The value of each substring is less than or equal to k.
Return the minimum number of substrings in a good partition of s. If no good partition of s exists, return -1.
Note that:
- The value of a string is its result when interpreted as an integer. For example, the value of "123" is 123 and the value of "1" is 1.
- A substring is a contiguous sequence of characters within a string.
Example 1:
Input: s = "165462", k = 60
Output: 4
Explanation: We can partition the string into substrings "16", "54", "6", and "2". Each substring has a value less than or equal to k = 60.
It can be shown that we cannot partition the string into less than 4 substrings.
Example 2:
Input: s = "238182", k = 5
Output: -1
Explanation: There is no good partition for this string.
Solution