Class Solution
- java.lang.Object
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- g2401_2500.s2466_count_ways_to_build_good_strings.Solution
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public class Solution extends Object
2466 - Count Ways To Build Good Strings.Medium
Given the integers
zero
,one
,low
, andhigh
, we can construct a string by starting with an empty string, and then at each step perform either of the following:- Append the character
'0'
zero
times. - Append the character
'1'
one
times.
This can be performed any number of times.
A good string is a string constructed by the above process having a length between
low
andhigh
( inclusive ).Return the number of different good strings that can be constructed satisfying these properties. Since the answer can be large, return it modulo
109 + 7
.Example 1:
Input: low = 3, high = 3, zero = 1, one = 1
Output: 8
Explanation:
One possible valid good string is “011”.
It can be constructed as follows: "" -> “0” -> “01” -> “011”.
All binary strings from “000” to “111” are good strings in this example.
Example 2:
Input: low = 2, high = 3, zero = 1, one = 2
Output: 5
Explanation: The good strings are “00”, “11”, “000”, “110”, and “011”.
Constraints:
1 <= low <= high <= 105
1 <= zero, one <= low
- Append the character
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Constructor Summary
Constructors Constructor Description Solution()
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description int
countGoodStrings(int low, int high, int zero, int one)
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