有人帮帮吗qwq
by TastyLemon @ 2023-02-19 12:43:12
哪题?
by jtshw @ 2023-02-19 12:44:47
@[jtshw](/user/737453) P1002
by TastyLemon @ 2023-02-19 12:45:59
@[Stillness_Cat](/user/260968)
~~我做过~~
这样不就行了
```cpp
#include<cstdio>
const int Const[2][9]={{0,-2,-1,1,2,2,1,-1,-2},{0,1,2,2,1,-1,-2,-2,-1}};
long long DP[21]={1};
bool mark[21][21];
int main() {
int nx,ny,hx,hy;
scanf("%d%d%d%d",&nx,&ny,&hx,&hy);
for(int i=0;i<9;++i)
if(hx+Const[0][i]>=0&&hx+Const[0][i]<=nx&&hy+Const[1][i]>=0&&hy+Const[1][i]<=ny)
mark[hx+Const[0][i]][hy+Const[1][i]]=1;
for(int i=0,j;i<=nx;++i)
for(DP[0]*=!mark[i][0],j=1;j<=ny;++j)
(DP[j]+=DP[j-1])*=!mark[i][j];
printf("%lld",DP[ny]);
return 0;
}
```
by jtshw @ 2023-02-19 12:50:01
@[jtshw](/user/737453) ...我只是想知道我哪错了
by TastyLemon @ 2023-02-19 12:54:50
被马控制的9个点中,有点处于上边界或者左边界的时候就会报错,比如4 8 2 2,答案应该是0(我用Python的,只能告诉你思路,不能直接给你代码)
by xhhy @ 2023-02-21 10:58:03