Class Solution
Hard
The appeal of a string is the number of distinct characters found in the string.
- For example, the appeal of
"abbca"
is3
because it has3
distinct characters:'a'
,'b'
, and'c'
.
Given a string s
, return the total appeal of all of its substrings.
A substring is a contiguous sequence of characters within a string.
Example 1:
Input: s = “abbca”
Output: 28
Explanation: The following are the substrings of “abbca”:
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Substrings of length 1: “a”, “b”, “b”, “c”, “a” have an appeal of 1, 1, 1, 1, and 1 respectively. The sum is 5.
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Substrings of length 2: “ab”, “bb”, “bc”, “ca” have an appeal of 2, 1, 2, and 2 respectively. The sum is 7.
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Substrings of length 3: “abb”, “bbc”, “bca” have an appeal of 2, 2, and 3 respectively. The sum is 7.
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Substrings of length 4: “abbc”, “bbca” have an appeal of 3 and 3 respectively. The sum is 6.
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Substrings of length 5: “abbca” has an appeal of 3. The sum is 3.
The total sum is 5 + 7 + 7 + 6 + 3 = 28.
Example 2:
Input: s = “code”
Output: 20
Explanation: The following are the substrings of “code”:
-
Substrings of length 1: “c”, “o”, “d”, “e” have an appeal of 1, 1, 1, and 1 respectively. The sum is 4.
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Substrings of length 2: “co”, “od”, “de” have an appeal of 2, 2, and 2 respectively. The sum is 6.
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Substrings of length 3: “cod”, “ode” have an appeal of 3 and 3 respectively. The sum is 6.
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Substrings of length 4: “code” has an appeal of 4. The sum is 4.
The total sum is 4 + 6 + 6 + 4 = 20.
Constraints:
1 <= s.length <= 105
s
consists of lowercase English letters.
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Constructor Summary
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Method Summary
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
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Constructor Details
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Solution
public Solution()
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Method Details
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appealSum
public long appealSum(java.lang.String s)
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