Given a binary string S of 0s and 1s of length N and M queries of the type [l, r], find the number of substrings of S(l to r) where there are even 1s.
Constraints:
N <= 10^5
M <= 10^5
1 <= l <= r <= N
Sample Input:
N = 5
S = 10001
M = 2
2 4
3 5
Sample Output:
6
3
Explanation:
For [2, 4] the 6 valid substrings are [2,2], [2,3], [2,4], [3,3], [3,4], [4,4]
For [3, 5] the 3 valid substrings are [3,3], [3,4], [4,4]