program string_8-

var s:string-

i,k:integer-

begin write(‘введите строку:’)-

readln(s)-

s:=’ ‘+s-k:=0-

for i:=1 to length(s) do

if (s[i]=’ ‘) and (s[i+1]=’b’) then k:=k+1-

writeln(k)-

Readln-

end.