选择插入代码，选择python，看不清啊
by Jasonshan10 @ 2023-05-26 21:29:32
可能是精度问题，改为
`k=int((s+w)*x//2)`
另外这样写更优雅
```python
l=list(map(int,input().split()))
s,e,x=l[0],l[1],l[2]
asd=e-s
w=s+asd*(x-1)
k=int((s+w)*x//2)
print(k)
```
by blsya23a2 @ 2023-08-04 09:06:28
@[VANE](/user/547858)
by blsya23a2 @ 2023-08-04 09:06:47