#include <bits/stdc++.h>
using namespace std;
const int mod = 998244353;
long long ncr[5001][5001], ways1, ways2, ways3, fact[5001];
void fill() {
  for (int i = 0; i <= 5000; i++) ncr[i][i] = ncr[i][0] = 1;
  for (int i = 1; i <= 5000; i++)
    for (int j = 1; j <= i; j++)
      ncr[i][j] = (ncr[i - 1][j] + ncr[i - 1][j - 1]) % mod;
  fact[0] = 1;
  for (int i = 1; i <= 5000; i++) fact[i] = (fact[i - 1] * i) % mod;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  fill();
  int a, b, c;
  cin >> a >> b >> c;
  for (int i = 0; i <= min(a, b); i++)
    ways1 = (ways1 + (((ncr[a][i] * ncr[b][i]) % mod) * fact[i]) % mod) % mod;
  for (int i = 0; i <= min(c, b); i++)
    ways2 = (ways2 + (((ncr[c][i] * ncr[b][i]) % mod) * fact[i]) % mod) % mod;
  for (int i = 0; i <= min(a, c); i++)
    ways3 = (ways3 + (((ncr[a][i] * ncr[c][i]) % mod) * fact[i]) % mod) % mod;
  ways1 = (ways1 * ways2) % mod;
  cout << (ways1 * ways3) % mod;
}
