B「木」迷雾森林

题目地址：

https://ac.nowcoder.com/acm/contest/5338/B

基本思路：

参考代码：

#pragma GCC optimize(2)
#pragma GCC optimize(3)
#include <bits/stdc++.h>
using namespace std;
#define IO std::ios::sync_with_stdio(false)
#define ll long long
#define rep(i, l, r) for (int i = l; i <= r; i++)
#define per(i, l, r) for (int i = l; i >= r; i--)
#define mset(s, _) memset(s, _, sizeof(s))
#define pb push_back
#define pii pair <int, int>
#define mp(a, b) make_pair(a, b)
#define INF 0x3f3f3f3f

inline int read() {
  int x = 0, neg = 1; char op = getchar();
  while (!isdigit(op)) { if (op == '-') neg = -1; op = getchar(); }
  while (isdigit(op)) { x = 10 * x + op - '0'; op = getchar(); }
  return neg * x;
}
inline void print(int x) {
  if (x < 0) { putchar('-'); x = -x; }
  if (x >= 10) print(x / 10);
  putchar(x % 10 + '0');
}
const int maxn = 3050;
int m,n,a[maxn][maxn];
int dp[maxn][maxn];
const int mod = 2333;
signed main() {
  m = read(),n = read();
  rep(i,1,m){
    rep(j,1,n) a[i][j] = read();
  }
  mset(dp,0);//初始是0;
  dp[m][1] = 1;
  for(int i = m ;i >= 1 ; i--){
    for(int j = 1; j <= n; j++){
      if(a[i][j] == 1) continue;//是树就跳过;
      if(i + 1 <= m) dp[i][j] += dp[i + 1][j];
      dp[i][j] %= mod;
      if(j - 1 >= 1) dp[i][j] += dp[i][j - 1];
      dp[i][j] %= mod;
    }
  }
  cout << dp[1][n] % mod << '\n';
  return 0;
}