$42$ children line up for the autumn outing. Counting from front to back, $Y$ is the $22$\textsuperscript{nd}. Counting from back to front, $M$ is the $22$\textsuperscript{nd}. How many children are there between $Y$ and $M$?  $$42$$个小朋友排成一队去秋游，从排头往后数，小$$Y$$是第$$22$$个，从排尾往前数，小$$M$$是第$$22$$个，小$$Y$$和小$$M$$中间有个人． 
选项为:A:$$0$$  B:$$1$$  C:$$2$$  D:$$3$$  请回答其中一个选项.