#include <bits/stdc++.h>
using namespace std;
const int N = 1e7 + 300;
const int maxn = 20010;
const int INF = 0x3f3f3f3f;
const double eps = 0.0000001;
const long long mod = 998244353;
long long n, m, x, y, z, k, cnt, t, len, q;
long long C[5010][5010];
long long fact[5010];
void init() {
  fact[0] = 1;
  for (int i = 1; i <= 5005; i++) fact[i] = (fact[i - 1] * i) % mod;
  C[0][0] = 1;
  for (int i = 1; i <= 5005; i++) {
    C[i][0] = 1;
    for (int j = 1; j <= i; j++) {
      C[i][j] = (C[i - 1][j] + C[i - 1][j - 1]) % mod;
      if (C[i][j] > mod) C[i][j] -= mod;
    }
  }
}
long long cul(long long a, long long b) {
  long long k = min(a, b);
  long long ans = 0;
  for (long long i = 0; i <= k; i++) {
    ans += (C[a][i] * C[b][i] % mod * fact[i]) % mod;
    ans %= mod;
  }
  return ans;
}
int main() {
  init();
  long long a, b, c;
  scanf("%lld%lld%lld", &a, &b, &c);
  printf("%lld", cul(a, b) % mod * cul(a, c) % mod * cul(b, c) % mod);
}
