#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <vector>
#include <string>
#include <cmath>
#include <set>
#include <map>
#include <deque>
#include <stack>
using namespace std;
typedef long long ll;
typedef vector<int> veci;
typedef vector<ll> vecl;
typedef pair<int, int> pii;
template <class T>
inline void read(T &ret) {char c;int sgn;if (c = getchar(), c == EOF) return ;while (c != '-' && (c < '0' || c > '9')) c = getchar();sgn = (c == '-') ? -1:1;ret = (c == '-') ? 0:(c - '0');while (c = getchar(), c >= '0' && c <= '9') ret = ret * 10 + (c - '0');ret *= sgn;return ;
}
inline void out(ll x) {if (x > 9) out(x / 10);putchar(x % 10 + '0');
}
const int mod = 998244353;
const int maxn = 2e5 + 10;
ll fac[maxn] = {0};
ll quickpow(ll a, ll b) {ll ans = 1, base = a;while (b) {if (b & 1) ans = ans * base % mod;base = base * base % mod;b >>= 1;}return ans;
}
ll C(ll n, ll m) {return fac[n] * quickpow(fac[m] * fac[n - m] % mod, mod - 2) % mod;
}
int main() {ll ans = 0, n, k;read(n), read(k);if (k > n - 1) {out(0);return 0;}fac[0] = fac[1] = 1;ll m = n - k;for (int i = 2; i < maxn; i++) fac[i] = (fac[i - 1] * i) % mod;for (int i = 0; i <= m; i++) {if (i % 2 == 0) ans += C(m, i) * quickpow(m - i, n) % mod;else ans = ans - C(m, i) * quickpow(m - i, n) % mod + mod;ans %= mod;}ans = (ans * C(n, m)) % mod;if (k) ans = (ans << 1) % mod;out(ans);return 0;
}

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