#include <bits/stdc++.h>
const long long Mod = 998244353;
using namespace std;
long long pre[5100], C[5100][5100];
long long ans = 1, res;
int n, a, b, c;
int main() {
  pre[0] = 1;
  for (int i = 1; i <= 5000; i++) {
    pre[i] = (pre[i - 1] * (long long)i) % Mod;
  }
  C[0][0] = 1;
  for (int i = 1; i <= 5000; i++) {
    C[i][0] = C[i][i] = 1;
    for (int j = 1; j < i; j++) {
      C[i][j] = (C[i - 1][j - 1] + C[i - 1][j]) % Mod;
    }
  }
  cin >> a >> b >> c;
  n = min(a, b), res = 0;
  for (int i = 0; i <= n; i++) {
    res = ((res + ((((C[a][i] * C[b][i]) % Mod) * pre[i]) % Mod)) % Mod);
  }
  ans = (ans * res) % Mod;
  n = min(c, b), res = 0;
  for (int i = 0; i <= n; i++) {
    res = ((res + ((((C[c][i] * C[b][i]) % Mod) * pre[i]) % Mod)) % Mod);
  }
  ans = (ans * res) % Mod;
  n = min(a, c), res = 0;
  for (int i = 0; i <= n; i++) {
    res = ((res + ((((C[a][i] * C[c][i]) % Mod) * pre[i]) % Mod)) % Mod);
  }
  ans = (ans * res) % Mod;
  cout << ans % Mod;
  return 0;
}
