public static boolean isSingleVarInequ(int[] a) {
		int nonZeroVars = 0;
		for (int i = 0; i < a.length; i++) {
			if (a[i] != 0)
				nonZeroVars++;
		}
		if (nonZeroVars > 1)
			return false;
		else
			return true;
	}