---
# System prepended metadata

title: Untitled

---

ログインユーザーの中で、プレミアムユーザーで、かつ、BANされてないユーザー

```python
login_ids = [5, 6, 7, 8, 9]  # 今ログインしてるユーザー
paid_ids = [2, 5, 8, 9]  # プレミアム登録してるユーザー
block_ids = [1, 3, 5]  # BANされたユーザー
```

```python
a,b,c = map(set, (login_ids, paid_ids, block_ids))
print(a&b-c)
```

```python
x = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
]
y = [
    [1, 3],
    [4, 6],
    [7, 9]
]
```

```python
y = []
for i, col in enumerate(zip(*x)):
    if i%2==0:
        y.append(col)
y = list(zip(*y))
```

```python
import numpy as np
x = np.array(x)
x[:,[0,2]]
```