P21010 [GeeksforGeeks] Queries on strings5636
普及
题目描述

Given a string str you have to answer several queries on that string. In each query you will be provided two values L and R and you have to find the number of distinct characters in the sub string from index L to index R (inclusive) of the original string.

Example 1:
Input: str = "abcbaed",
Query = {{1,4},{2,4},{1,7}}
Output: {3,2,5}
Explanation: For the first query distinct
characters from [1, 4] are a, b and c.
For the second query distinct characters from
[2, 4] are b and c.
For the third query distinct characters from
[1, 7] are a, b, c, d and e.

Your Task:
You don't need to read or print anyhting. Your task is to complete the function SolveQueries() which takes str and Query as input parameter and returns a list containing answer for each query.

Expected Time Complexity: O(max(26*length of str, 26 * No of queries))
Expected Space Complexity: O(26 * length of str)

Constraints:
1 <= |str| <= 10^{5}
1 <= No of Queries <= 10^{4}
1 <= L_{i} <= R_{i} <= |str|

输入格式

见题面

输出格式

见题面

样例输入
str = "abcbaed", Query = {{1,4},{2,4},{1,7}}
样例输出
{3,2,5}