program raf105;
var
a,i,j,s: integer;
f,st: string;
inA,inB: boolean;
begin
readln(a);
readln(f);
i:=1;
while i < length(f)-1 do
begin
st:= f[i] + f[i+1];
inA:= False;
inB:= False;
for j:=1 to length(st)-1 do
begin
if st[j] = 'a' then inA:= True;
if st[j] = 'b' then inB:= True;
end;
if (not inA) or (not inB) then
if st = 'bb' then
f[i+1]:= 'a'
else
f[i+1]:= 'b';
s:= s+1;
i+= 2;
end;
writeln(s);
for i:=1 to length(f)-1 do
write(f[i],' ');
end.
PascalABC
