#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const long long INFF = 0x3f3f3f3f3f3f3f3fll;
const int MAX = 4e5 + 10;
const long long MOD = 998244353;
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
template <typename T>
inline T abs(T a) {
  return a > 0 ? a : -a;
}
template <class T>
inline void read(T& num) {
  bool start = false, neg = false;
  char c;
  num = 0;
  while ((c = getchar()) != EOF) {
    if (c == '-')
      start = neg = true;
    else if (c >= '0' && c <= '9') {
      start = true;
      num = num * 10 + c - '0';
    } else if (start)
      break;
  }
  if (neg) num = -num;
}
inline long long powMM(long long a, long long b, long long M) {
  long long ret = 1;
  a %= M;
  while (b) {
    if (b & 1) ret = ret * a % M;
    b >>= 1;
    a = a * a % M;
  }
  return ret;
}
void open() { freopen("out.txt", "w", stdout); }
const int MAXN = 1e5 + 5;
long long fac[MAXN], inv[MAXN];
long long quick(long long a, long long b) {
  long long an = 1LL;
  while (b) {
    if (b & 1) {
      an = an * a % MOD;
    }
    a = a * a % MOD;
    b /= 2;
  }
  return an % MOD;
}
long long dp[5005][5005];
long long an, a, b, c;
inline long long dfs(long long s, long long yu) {
  if (yu < 0) return 0;
  if (!s) return 1LL;
  long long re = 0;
  if (dp[s][yu] != -1) return dp[s][yu];
  re = (yu * dfs(s - 1, yu - 1) % MOD + dfs(s - 1, yu)) % MOD;
  dp[s][yu] = re;
  return re;
}
long long solve(long long x, long long y) { return dfs(x, y); }
int main() {
  memset(dp, -1, sizeof(dp));
  cin >> a >> b >> c;
  an = 1LL;
  cout << solve(a, b) * solve(b, c) % MOD * solve(c, a) % MOD;
  return 0;
}
