#include <bits/stdc++.h>
using namespace std;
const int maxn = 1000005;
const int mod = 998244353;
long long f[5009];
long long c[5009][5009];
long long ch(int a, int b) {
  long long sum = 0;
  for (int i = 0; i <= a && i <= b; i++) {
    sum += ((c[a][i] * c[b][i] % mod) * f[i] % mod);
  }
  return sum % mod;
}
int main() {
  f[0] = f[1] = 1;
  for (int i = 2; i <= 5000; i++) {
    f[i] = f[i - 1] * i % mod;
  }
  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] + c[i - 1][j - 1]) % mod;
    }
  }
  int a, b, c;
  while (~scanf("%d%d%d", &a, &b, &c)) {
    long long ans = 1;
    ans = ans * ch(a, b);
    ans %= mod;
    ans = ans * ch(a, c);
    ans %= mod;
    ans = ans * ch(b, c);
    ans %= mod;
    printf("%I64d\n", ans);
  }
  return 0;
}
