#include <bits/stdc++.h>
using namespace std;
const int maxn = 5e3 + 10;
const int mod = 998244353;
long long mul[maxn];
long long inv[maxn];
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 mult(int a, int b) {
  int len = min(a, b);
  long long ans = 0;
  for (int i = 0; i <= len; i++)
    ans += C(a, i) * C(b, i) % mod * mul[i] % mod, ans %= mod;
  return ans;
}
int main() {
  init();
  int a, b, c;
  cin >> a >> b >> c;
  long long ans = mult(a, b) * mult(b, c) % mod * mult(c, a) % mod;
  cout << ans << endl;
  return 0;
}
