@ 类似于他的代码

#include <bits/stdc++.h>
#define int long long
using namespace std;

const int mod = 998244353;

int n, m;
int a[105][2005];
int f[105][205];

int qm(int x) {
    if (x >= mod) {
        x -= mod;
    }
    return x;
}

void ad(int &s, int t) {
    s = qm(s + t);
    return ;
}

signed main() {
    freopen("meal.in", "r", stdin);
    freopen("meal.out", "w", stdout);
    scanf("%lld%lld", &n, &m);
    int ans = 1;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            scanf("%lld", &a[i][j]);
            a[i][0] = qm(a[i][0] + a[i][j]);
        }
        ans = ans * qm(a[i][0] + 1) % mod;
    }
    ans = qm(ans - 1 + mod);
    for (int o = 1; o <= m; o++) {
        for (int i = 0; i <= n; i++) {
            for (int j = 0; j <= 2 * n; j++) {
                f[i][j] = 0;
            }
        }
        f[0][n] = 1;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j <= 2 * n; j++) {
                if (f[i][j]) {
                    ad(f[i + 1][j], f[i][j]);
                    ad(f[i + 1][j + 1],f[i][j] * a[i + 1][o] % mod);
                    ad(f[i + 1][j - 1],f[i][j] * qm(a[i + 1][0] - a[i + 1][o] + mod) % mod);
                }
            }
        }
        for (int j = n + 1; j <= 2 * n; j++) {
            ans = qm(ans - f[n][j] + mod);
        }
    }
    printf("%lld", ans);
    return 0;
}

@ 不知道：（