错误代码```cpp #include #include using namespace std; int main(){ int x1,y1,x2,y2; cin>>x1>>y1>>x2>>y2; vector<vector>dp(x1+1,vector(y1+1,0)); for(int i=0;i<=x1;i++)dp[i][0]=1; for(int j=0;j<=y1;j++)dp[0][j]=1; if (x2 + 2 <= x1 && y2 + 1 <= y1) dp[x2 + 2][y2 + 1] = 0; if (x2 + 2 <= x1) dp[x2 + 2][y2] = 0; if (x2 + 1 <= x1 && y2 - 2 >= 0) dp[x2 + 1][y2 - 2] = 0; for(int i=1;i<=x1;i++){ for(int j=1;j<=y1;j++){ if(dp[i][j]!=0){ dp[i][j]=dp[i-1][j]+dp[i][j-1]; } } } cout<<dp[x1][y1]; }