@Test
public void findSumTuples() {
assertThat(arrayOperations.findSumTuples(null, 10), is(new int[0][]));
assertThat(arrayOperations.findSumTuples(new int[0], 10), is(new int[0][]));
assertThat(arrayOperations.findSumTuples(new int[0], -1), is(new int[0][]));
assertThat(arrayOperations.findSumTuples(new int[] {1, 2, 3}, 10), is(new int[0][]));
assertThat(arrayOperations.findSumTuples(new int[] {1, 2, 3}, -1), is(new int[0][]));
assertThat(arrayOperations.findSumTuples(new int[] {3, 5}, 8), is(new int[][] {{3, 5}}));
assertThat(
arrayOperations.findSumTuples(new int[] {1, 2, 4, -1}, 3),
is(new int[][] {{-1, 4}, {1, 2}}));
assertThat(
arrayOperations.findSumTuples(new int[] {1, 2, 3, 4, 5, 6, 7, 10, -2, -7}, 3),
is(new int[][] {{1, 2}, {-2, 5}, {-7, 10}}));
}
