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CF1155A.Reverse a Substring
Reverse a Substring
You are given a string consisting of lowercase Latin letters.
Let's define a substring as a contiguous subsegment of a string. For example, "acab" is a substring of "abacaba" (it starts in position and ends in position ), but "aa" or "d" aren't substrings of this string. So the substring of the string from position to position is .
You have to choose exactly one of the substrings of the given string and reverse it (i. e. make ) to obtain a string that is less lexicographically. Note that it is not necessary to obtain the minimum possible string.
If it is impossible to reverse some substring of the given string to obtain a string that is less, print "NO". Otherwise print "YES" and any suitable substring.
String is lexicographically less than string , if either is a prefix of (and ), or there exists such (), that , and for any () . Here denotes the length of the string . The lexicographic comparison of strings is implemented by operator < in modern programming languages.
Input
The first line of the input contains one integer () — the length of .
The second line of the input contains the string of length consisting only of lowercase Latin letters.
Output
If it is impossible to reverse some substring of the given string to obtain a string which is lexicographically less, print "NO". Otherwise print "YES" and two indices and () denoting the substring you have to reverse. If there are multiple answers, you can print any.
Note
In the first testcase the resulting string is "aacabba".
Samples
7
abacaba
YES
2 5
6
aabcfg
NO
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