@Test public void basicTest1() { int[] arr = {3, 2, 1}; Assert.assertEquals(3, countInversion.solve(arr)); }
public int solve(int[] arr) { return -1; }
CountInversion { public int solve(int[] arr) { return -1; } }
CountInversion { public int solve(int[] arr) { return -1; }  }
CountInversion { public int solve(int[] arr) { return -1; }  int solve(int[] arr); }
CountInversion { public int solve(int[] arr) { return -1; }  int solve(int[] arr);  }