const int BOY=1;          //?????1????2????0
const int GIRL=2;
const int NONE=0;
int line[100]={NONE};     //????line????
int n=0;                  //???n
void leave()              //??leave??
{
	int last=-1;          //??last??????????
	for(int i=0;i<n;i++)  //????
	{
		if(line[i]==BOY)  //????????last???????
			last=i;
		if(line[i]==GIRL&&last>=0)  //????????????????????????????????
		{
			line[i]=line[last]=NONE;
			cout<<last<<' '<<i<<endl;
			leave();
		}
	}
}			
int main()
{
	char boy,c;       //??boy????????c???????
	boy=getchar();    //????????
	line[0]=BOY;      //???????
	n++;              //n?1
	for(;;)           //??
	{
		c=getchar();  //????
		if(c=='\n')break;//???????????????1??????????????
		n++;
		if(c==boy)
			line[n-1]=BOY;
		else line[n-1]=GIRL;
	}
	leave();           //??????
	return 0;
}
