- Given an array of coordinates, return the number of right angles (composed of 3 points) e that the coordinates can form (lines should be paralell to the x or y axis) . (0,0), (2,0) (0,2) is an example of a right angle.
- Design an order tracking system.
- Given a list of object (id, coordinates) and a list of (id1, id2) which indicates a bidirectional bridge, and start id and end id, return True if there is a way to get from start to end

3b. Take an extra input j, which denotes the amount of jumps that can be made ( from (0,0) to (0,2) is possible if j =2 ), and figure out if its still possible to get from start to end.

3 explanation:

inputs are:

- list of objects (call this
`platforms`

). the order is`(id, xcoord, ycoord)`

```
[
(0, 1, 2)
(1, 2, 3)
(2, 3, 4)
(3, 3, 5)
]
```

- list of tuple of ids (call this
`bridges`

).`(0,1)`

means there is an edge between platform 0 and platform 1.

```
[
(0,1)
(1,2)
(2,3)
]
```

- start id

```
0
```

- end id

```
2
```

output is:

True/False (depending on getting from start platform to end platform is possible)

for the next question, Take an extra input `j`

that indicates number of jumps that can be made from any platform. This jump can span either x axis or y axis.

E.g.

Platforms `[(0, 1, 2), (1, 1, 5), (2, 3, 5)]`

Bridges `[(1,2)]`

start `0`

end `2`

j `3`

Returns True

Because from platform 0, there are no bridges but j is 3, so you can jump to platform 1. From platform 1 to 2, there is a bridge so you can go to platform 2.

My approaches:

- My approach was a n^2 time, n^2 space complexity solution. Traverse every point to all points with same x axis, then from the second point, traverse every point to all points with same y axis. Do the same but the axises flipped. Definitely was not the optimal solution.
- Did some API designs, system diagrams, but the interviewer did not seem satisfied.
- Solved the first part with DFS. Verbally talked about the solution for the follow up question but no time to code it. Definitely was not an optimized solution

Overall I did not expect to get these kind of questions; I thought i was prepared on most algorithms like string, arrays, dp, trees, and graphs, but obviously not enough to comfortably solve these kind of questions.