B'You are given a string s , consisting of n letters, each letter is either 'a ' or 'b '. The letters in the string are numbered from 1 to n . s[l; r] is a continuous substring of letters from index l to r of the string inclusive. A string is called balanced if the number of letters 'a ' in it is equal to the number of letters 'b '. For example, strings "baba" and "aabbab" are balanced and strings "aaab" and "b" are not. Find any non-empty balanced substring s[l; r] of string s . Print its l and r ( 1 <= l <= r <= n ). If there is no such substring, then print -1 -1 . The first line contains a single integer t ( 1 <= t <= 1000 ) -- the number of testcases. Then the descriptions of t testcases follow. The first line of the testcase contains a single integer n ( 1 <= n <= 50 ) -- the length of the string. The second line of the testcase contains a string s , consisting of n letters, each letter is either 'a ' or 'b '. For each testcase print two integers. If there exists a non-empty balanced substring s[l; r] , then print l r ( 1 <= l <= r <= n ). Otherwise, print -1 -1 . In the first testcase there are no non-empty balanced subtrings. In the second and third testcases there are multiple balanced substrings, including the entire string "abbaba" and substring "baba". '...