好乱emmmmm
by lcglcg @ 2019-08-07 11:05:37
希望更丰富的展现？[使用Markdown](https://www.luogu.org/wiki/show?name=%E5%B8%AE%E5%8A%A9%EF%BC%9Amarkdown)
by Elzat @ 2019-08-07 11:05:44
@[Genoa21](/space/show?uid=126053)
```cpp
#include<stdio.h>
long long a[101][101];
int b[101][101];
int main(){
int n,m,x,y,i,j;
int dx[9]={0,2,1,-1,-2,-2,-1,1,2};
int dy[9]={0,1,2,2,1,-1,-2,-2,-1};
scanf("%d%d%d%d",&n,&m,&x,&y);
b[x][y]=1;a[0][0]=1;
for(i=1;i<=8;i++){
if((x+dx[i]>=0)&&(x+dx[i]<=n)&&(y+dy[i]>=0)&&(y+dy[i]<=m)){
b[x+dx[i]][y+dy[i]]=1;
}
}
for(j=1;j<=m;j++){
if(b[0][j]==0){
a[0][j]=a[0][j-1];
}
}
for(i=1;i<=n;i++){
if(b[i][0]==0){
a[i][0]=a[i-1][0];
}
}
for(i=1;i<=n;i++){
for(j=1;j<=m;j++){
if(b[i][j]==0){
a[i][j]=a[i-1][j]+a[i][j-1];
}
}
}
printf("%lld\n",a[n][m]);
return 0;
}
```
by G_M_H @ 2019-08-07 11:36:14
一个递推吧。貌似可以叫做DP；从之前两个方向把状态转移过来。
by G_M_H @ 2019-08-07 11:37:29
@[G_M_H](/space/show?uid=130029) 谢谢dalao
by qqqevinxxz @ 2019-08-10 20:50:15