There are some sequences like:
op_num: [start, end], type
1: [0, 10], Wrtie // op_1 will write the range [0,10]
2: [5, 10], Read // op_2 will read the range [9,10]
3: [6, 7], Read
4: [6, 7], Write
Now I am going to write an algorithm to get the dependencies of them.
For op_2, since [9,10] is just wrote by op_1, so op_2 has to wait for op_1 finishing.
For op_3, althouth [6,7] is also just read by op_2，but since read op does not have to wait read op, op_3 only need to wait for op_1.
For op_4, [6,7] is read by 'op_2 and 'op_3, and is wrote by op_1, but since op_2 and op_3 would wait for op_1, so op_4 only need to wait for op_2 and op_3 explicitly.
The final goal is to generate the waiting sequences, like:
2 --> 1
3 --> 1
4 --> 2
4 --> 3
I'm trying to find an algorithm as fast as possible. I think maybe segment tree could help? But I'm not able to firgure it out.
