I have two tensor

```
T = torch.tensor([20, 4, 5, 9, 22, 5, 50, 9, 45, 5])
I = torch.tensor([ 0, 2, 3, 1, 1, 3, 1, 3, 0, 0])
```

Each with same number of elements. Tensor ‘I’ has numbers ranging from 0 to 3. I have to make 4 tensors sampling from the tensor ‘T’ according to numbers in tensor ‘I’,

such that my output would be:

```
a0 = [20, 45, 5]
a1 = [9, 22, 50 ]
a2 = [4]
a3 = [5, 5, 9]
```

As my actual tensors are very big, what is the most efficient and fastest way to do it using GPU??