肯定不是算法问题，因为可以有60分，而且把语言换成python（自带高精）后顺利AC.
```python
f=[]
for i in range(30):
a=[]
for j in range(30):
a.append(0)
f.append(a)
Bx,By,Mx,My=input().split()
Bx=int(Bx)
By=int(By)
Mx=int(Mx)
My=int(My)
f[Mx][My] = -1
if (Mx >= 2 and My >= 1):
f[Mx - 2][My - 1] = -1
if (Mx >= 1 and My >= 2):
f[Mx - 1][My - 2] = -1
if (Mx >= 1):
f[Mx - 1][My + 2] = -1
if (Mx >= 2):
f[Mx - 2][My + 1] = -1
f[Mx + 1][My + 2] = -1
f[Mx + 2][My + 1] = -1
if (My >= 2):
f[Mx + 1][My - 2] = -1
if (My >= 1):
f[Mx + 2][My - 1] = -1
f[Bx][By+1]=1
for i in range(Bx,-1,-1):
for j in range(By,-1,-1):
if f[i][j] != -1:
right=down=0
if (f[i + 1][j] != -1):
right = f[i + 1][j]
if (f[i][j + 1] != -1):
down = f[i][j + 1]
f[i][j]=down+right
print(f[0][0])
```
by tcs06358 @ 2020-01-05 04:29:19
@[tcs06358](/user/25332)
然而$long long$[可过](https://www.luogu.com.cn/record/28984244)
by VTloBong @ 2020-01-05 07:01:04
那为什么我的爆掉了啊
by tcs06358 @ 2020-01-05 07:09:01
@[123456L](/user/212187)
by tcs06358 @ 2020-01-05 07:09:12
@[tcs06358](/user/25332) 因为您写挂了orz
by He_Ren @ 2020-01-05 07:29:23
@[tcs06358](/user/25332)
`int right,down;`->`long long right,down;`
by hht2005 @ 2020-01-05 07:30:38
@[hht2005](/user/151722) 万分感谢！！！居然忘了这一点！！！！！！
by tcs06358 @ 2020-01-05 07:57:37
实在不行试试__int128？
by impuk @ 2020-01-05 09:23:04
我觉得直接#define int long long比较爽
by 不摇碧莲 @ 2020-01-05 09:25:56
@[不摇碧莲](/user/275107) 2333
by lzhxdxz @ 2020-01-05 09:55:28