ECHO: []
ECHO: [1]
ECHO: [2]
ECHO: [2]
ECHO: []
ECHO: [1]
ECHO: [0, 1]
ECHO: [0, 1]
ECHO: []
ECHO: []
ECHO: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
ECHO: [[0, 10], [0, 11], [0, 12], [0, 13], [1, 10], [1, 11], [1, 12], [1, 13], [2, 10], [2, 11], [2, 12], [2, 13], [3, 10], [3, 11], [3, 12], [3, 13]]
ECHO: [[0, 10], [0, 11], [0, 12], [0, 13], [1, 10], [1, 11], [1, 12], [1, 13], [2, 10], [2, 11], [2, 12], [2, 13], [3, 10], [3, 11], [3, 12], [3, 13]]
ECHO: [[[0, 10], [0, 11], [0, 12], [0, 13]], [[1, 10], [1, 11], [1, 12], [1, 13]], [[2, 10], [2, 11], [2, 12], [2, 13]], [[3, 10], [3, 11], [3, 12], [3, 13]]]
ECHO: [[[1, 10], [1, 12], [1, 13]]]
ECHO: [[[0, 10], [0, 11], [0, 12], [0, 13]], [[1, 10], [1, 11], [1, 12], [1, 13]], [[2, 10], [2, 11], [2, 12], [2, 13]], [[3, 10], [3, 11], [3, 12], [3, 13]]]
ECHO: [[0, 10], [0, 11], [0, 12], [0, 13], [1, 10], [1, 11], [1, 12], [1, 13], [2, 10], [2, 11], [2, 12], [2, 13], [3, 10], [3, 11], [3, 12], [3, 13]]
ECHO: [0, 10, 0, 11, 0, 12, 0, 13, 1, 10, 1, 11, 1, 12, 1, 13, 2, 10, 2, 11, 2, 12, 2, 13, 3, 10, 3, 11, 3, 12, 3, 13]
ECHO: [[0, 10], [0, 11], [0, 12], [0, 13], [1, 10], [1, 11], [1, 12], [1, 13], [2, 10], [2, 11], [2, 12], [2, 13], [3, 10], [3, 11], [3, 12], [3, 13]]
ECHO: [0, 10, 0, 11, 0, 12, 0, 13, 1, 10, 1, 11, 1, 12, 1, 13, 2, 10, 2, 11, 2, 12, 2, 13, 3, 10, 3, 11, 3, 12, 3, 13]
ECHO: [0, 1]
ECHO: [0, 1]
ECHO: [0, 1]
ECHO: [[0, 0], [1, 0], [2, 0], [1, 1], [2, 1]]
ECHO: [[0, 0], [1, 0], [2, 0], [1, 1], [2, 1]]
ECHO: [[0, 0], [1, 0], [2, 0], [1, 1], [2, 1]]