#include <bits/stdc++.h>
const int MAXINT = 2147483640;
const long long MAXLL = 9223372036854775800LL;
const long long MAXN = 1000000;
const long long MOD = 998244353;
using namespace std;
long long dp[5005][5005];
long long fact[MAXN];
long long P(long long n, long long k) {
  long long res = 1;
  for (long long i = (n - k) + 1; i <= n; ++i) res = (res * i) % MOD;
  return res;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long long a, b, c, ans1 = 0, ans2 = 0, ans3 = 0;
  cin >> a >> b >> c;
  for (long long i = 0; i <= 5000; ++i) {
    dp[i][0] = 1;
    for (long long j = 1; j <= i; ++j)
      dp[i][j] = (dp[i - 1][j] + dp[i - 1][j - 1]) % MOD;
  }
  for (long long i = 0; i <= min(a, b); ++i)
    ans1 = (ans1 + (dp[b][i] * P(a, i)) % MOD) % MOD;
  for (long long i = 0; i <= min(a, c); ++i)
    ans2 = (ans2 + (dp[a][i] * P(c, i)) % MOD) % MOD;
  for (long long i = 0; i <= min(b, c); ++i)
    ans3 = (ans3 + (dp[c][i] * P(b, i)) % MOD) % MOD;
  cout << ((ans1 * ans2) % MOD * ans3) % MOD << '\n';
  return 0;
}
