public static boolean esNumeroPosNeg(String string) {
		int cantp=0;
		int pos=0;
		int indiceSigno=0;
		while (pos<string.length()) {
			if(string.charAt(pos)=='-'){
				cantp++;
				indiceSigno=pos;
			}	
			pos++;
		}
		if(cantp<=1){
			if(indiceSigno==0)
				return true;
			else
				return false;
		}else
			return false;
	}