#include <bits/stdc++.h>
using namespace std;
const int maxn = 20000 + 10;
const int MOD = 998244353;
long long fact[maxn], inv[maxn];
long long power_mod(long long x, long long n) {
  long long ret = 1;
  while (n) {
    if (n & 1) ret = ret * x % MOD;
    x = x * x % MOD;
    n >>= 1;
  }
  return ret;
}
void init() {
  fact[0] = fact[1] = 1;
  inv[0] = inv[1] = 1;
  for (int i = 2; i < maxn; ++i) {
    fact[i] = i * fact[i - 1] % MOD;
    inv[i] = power_mod(fact[i], MOD - 2);
  }
}
long long C(long long n, long long m) {
  return fact[n] * inv[n - m] % MOD * inv[m] % MOD;
}
long long A(long long n, long long m) { return fact[n] * inv[n - m] % MOD; }
long long solve(int a, int b) {
  int ret = 0;
  for (int i = 0; i <= min(a, b); ++i) ret = (ret + C(a, i) * A(b, i)) % MOD;
  return ret;
}
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  long long ans = 1;
  long long tmp1 = 0;
  long long tmp2 = 0;
  long long tmp3 = 0;
  init();
  std::cout << (solve(a, b) * solve(b, c) % MOD * solve(a, c) % MOD) << '\n';
  return 0;
}
