[ { "n": 7, "m": 8, "volcanoes": [ [ 1, 6 ], [ 2, 6 ], [ 3, 5 ], [ 3, 6 ], [ 4, 3 ], [ 5, 1 ], [ 5, 2 ], [ 5, 3 ] ] }, { "n": 4, "m": 2, "volcanoes": [ [ 1, 3 ], [ 1, 4 ] ] }, { "n": 2, "m": 2, "volcanoes": [ [ 1, 2 ], [ 2, 1 ] ] }, { "n": 6, "m": 3, "volcanoes": [ [ 2, 2 ], [ 3, 3 ], [ 4, 4 ] ] } ]