Method previousElement

java/Chapter 3/Question3_1/QuestionB.java:55–61

(int index)

	}
	
	public static int previousElement(int index) {
		if (index == 0) {
			return total_size - 1;
		} else {
			return index - 1;
		}
	}
	
	public static void shift(int stackNum) {
		StackData stack = stacks[stackNum];