#gets.split(" ").map!(&:to_i)
def fact(x);return 1 if x<2;(1..x).inject(:*);end
def combi(x,k);fact(x)/(fact(k)*fact(x-k));end

chr=gets.chars

w=chr.inject(0){|s,e|s+(e=="w" ? 1 : 0)}

n=0
chr.each{|e|
    break if w<=1
    n+=combi(w,2) if e=="c"
    w-=1 if e=="w"
}
p n