#include <bits/stdc++.h>
using namespace std;
long long mul[100010], inv[100010];
const int mod = 998244353;
const int maxn = 5050;
void init() {
  mul[0] = 1;
  for (int i = 1; i < maxn; i++) mul[i] = (mul[i - 1] * i) % mod;
  inv[0] = inv[1] = 1;
  for (int i = 2; i < maxn; i++)
    inv[i] = (long long)(mod - mod / i) * inv[mod % i] % mod;
  for (int i = 1; i < maxn; i++) inv[i] = (inv[i - 1] * inv[i]) % mod;
}
long long C(int n, int m) { return mul[n] * inv[m] % mod * inv[n - m] % mod; }
long long f(long long a, long long b) {
  long long ans = 0;
  for (int i = 0; i <= min(a, b); i++)
    ans = (ans + C(a, i) * C(b, i) % mod * mul[i] % mod) % mod;
  return ans;
}
int main() {
  int a, b, c;
  init();
  cin >> a >> b >> c;
  cout << f(a, b) * f(a, c) % mod * f(b, c) % mod << endl;
}
