<s>[INST] Step 1: Analyze the problem

We are given a list of unique integers, and we need to find the maximum rectangular area that can be made from these integers.

### Step 2: Outline the solution strategy

To find the maximum rectangular area, we will use the concept of histograms and the largest rectangle problem. The idea is to treat the integers as heights of bars in a histogram and find the maximum area of a rectangle that can be formed using these bars.

### Step 3: Implement a histrogram using Java

```java
public class MaximalRectangle {
    public int maximalRectangle(char[][] matrix) {
        if (matrix == null || matrix.length == 0 || matrix[0].length == 0)
            return 0;
        int[] height = new int[matrix[0].length];
        int maxArea = 0;
        
        for (int row = 0; row < matrix.length; row++) {
            for (int col = 0; col < matrix[0].length; col++) {
                height[col] = matrix[row][col] == '0'?[/INST]