#include <bits/stdc++.h>
using namespace std;
long long dp[5001][5001];
int a, b, c;
int main() {
  cin >> a >> b >> c;
  for (int i = 0; i < 5001; i++) {
    for (int j = 0; j < 5001; j++) {
      if (i == 0 || j == 0)
        dp[i][j] = 1;
      else
        dp[i][j] =
            (dp[i][j - 1] + (i * dp[i - 1][j - 1]) % 998244353) % 998244353;
    }
  }
  cout << (((dp[a][b] * dp[b][c]) % 998244353) * dp[a][c]) % 998244353 << endl;
  return 0;
}
