3144. Minimum Substring Partition of Equal Character Frequency
Given a string s, you need to partition it into one or more balanced substrings. For example, if s == "ababcc" then ("abab", "c", "c"), ("ab", "abc", "c"), and ("ababcc") are all valid partitions, but ("a", "bab", "cc"), ("aba", "bc", "c"), and ("ab", "abcc") are not. The unbalanced substrings are bolded.
Return the minimum number of substrings that you can partition s into.
Note: A balanced string is a string where each character in the string occurs the same number of times.
Example 1:
Input: s = "fabccddg"
Output: 3
Explanation:
We can partition the string s into 3 substrings in one of the following ways: ("fab, "ccdd", "g"), or ("fabc", "cd", "dg").
Example 2:
Input: s = "abababaccddb"
Output: 2
Explanation:
We can partition the string s into 2 substrings like so: ("abab", "abaccddb").
Constraints:
1 <= s.length <= 1000sconsists only of English lowercase letters.
Hints
Hint 1
dp[i] be the minimum number of partitions for the prefix ending at index i + 1.Hint 2
dp[i] can be calculated as the min(dp[j]) over all j such that j < i and word[j+1…i] is valid.