#include <bits/stdc++.h>
using namespace std;
long long mod = 998244353;
long long f[500005];
long long pow(int a, int b, int MOD) {
  long long x = 1, y = a;
  while (b > 0) {
    if (b % 2 == 1) {
      x = (x * y);
      if (x > MOD) x %= MOD;
    }
    y = (y * y);
    if (y > MOD) y %= MOD;
    b /= 2;
  }
  return x;
}
long long InverseEuler(int n, int MOD) { return pow(n, MOD - 2, MOD); }
long long C(int n, int r, int MOD) {
  return (f[n] *
          ((InverseEuler(f[r], MOD) * InverseEuler(f[n - r], MOD)) % MOD)) %
         MOD;
}
void fun() {
  f[0] = 1;
  for (int i = 1; i <= 500000; i++) {
    f[i] = (f[i - 1] * i) % mod;
  }
}
int main() {
  fun();
  int a, b, c;
  cin >> a >> b >> c;
  long long ans = 1;
  long long x = 0, y = 0, z = 0;
  for (int i = 0; i <= min(a, b); i++) {
    x = (x + ((C(a, i, mod) * C(b, i, mod)) % mod) * f[i]) % mod;
  }
  for (int i = 0; i <= min(a, c); i++) {
    y = (y + ((C(a, i, mod) * C(c, i, mod)) % mod) * f[i]) % mod;
  }
  for (int i = 0; i <= min(c, b); i++) {
    z = (z + ((C(c, i, mod) * C(b, i, mod)) % mod) * f[i]) % mod;
  }
  ans = ((x * y) % mod) * z;
  cout << ans % mod << endl;
}
