Lazy student
Stepan considers himself a brilliant programmer. He believes he already knows everything taught in programming classes. So, instead of paying attention to the teacher, Stepan has invented a game for himself: he takes a newspaper and crosses out all the letters in the text that have "holes." For instance, he crosses out letters like 'o' and 'a', but leaves 'w' and 'c' untouched. Stepan thinks this exercise helps him improve his attentiveness. However, he needs a way to ensure he hasn't made any mistakes. He figures that verifying the total number of crossed-out letters is sufficient. Therefore, he asks you to write a program that calculates how many letters should be crossed out in the given text.
Input
You are given a string consisting of lowercase Latin letters and spaces—the text Stepan brought to class. The string's length does not exceed 100,000 characters.
Output
Output the number of letters that should be crossed out.