static boolean esSlump(char[] str, int cotaInf, int cotaSup){
		if(cotaInf >= cotaSup)return false;
		if(str[cotaInf] != 'E' && str[cotaInf] != 'D')return false;
		int posIni = cotaInf+1;
		if(str[posIni] != 'F')return false;
		for(;posIni <= cotaSup; posIni++)if(str[posIni]!='F')break;
		if(posIni>cotaSup)return false;
		return (posIni == cotaSup && str[cotaSup] == 'G') || esSlump(str, posIni, cotaSup); 
	}