#include <bits/stdc++.h>
using namespace std;
const long long int N = 2e3 + 20;
const long long int mod = 998244353;
long long int dp[5050][5050];
bool mark[N * N + 10];
int32_t main() {
  ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);
  for (int i = 0; i <= 5000; ++i)
    for (int j = 0; j <= 5000; j++) {
      if (!i || !j)
        dp[i][j] = 1;
      else
        dp[i][j] = (dp[i - 1][j] + j * dp[i - 1][j - 1]) % mod;
    }
  long long int a, b, c;
  cin >> a >> b >> c;
  return cout << (((dp[a][b] * dp[a][c]) % mod) * dp[b][c]) % mod, 0;
}
