String Changes

Have the function StringChanges(str) take the str parameter being passed, which will be a string containing letters from the alphabet, and return a new string based on the following rules. Whenever a capital M is encountered, duplicate the previous character (then remove the M), and whenever a capital N is encountered remove the next character from the string (then remove the N). All other characters in the string will be lowercase letters. For example: "abcNdgM" should return "abcgg". The final string will never be empty.

Examples

Input: "MrtyNNgMM"
Output: rtyggg

Input: "oMoMkkNrrN"
Output: ooookkr