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mystery2d3

Language/Type: Java 2D arrays array mystery
Author: Marty Stepp (on 2021/04/02)

Consider the following method: 

            public Set mystery3(int[][] data) {
                Set result = new TreeSet<>();
                for (int i = 0; i < data.length; i++) {
                    for (int j = 0; j < data[i].length; j++) {
                        result.add(i * 10 + data[i][j]);
                    }
                }
                return result;
            }

In the left-hand column below are specific two-dimensional arrays. You are to indicate in the right-hand column what values would be stored in the set returned by method mystery3 if the array in the left-hand column is passed as a parameter to mystery3. Set elements should be listed in proper order as a comma-separated bracketed list, as in [3, 18, 25].

[[1, 2], [3, 4]]
[[7], [], [8, 8, 9, 10]]
[[3, 14], [5, 13, 4], [4, 3, 1]]

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