#include <bits/stdc++.h>
using namespace std;
long long a, b, c, fac[5100], i, co[5100][5100], j, tmp, ans;
int main() {
  scanf("%lld %lld %lld", &a, &b, &c);
  fac[0] = 1;
  for (i = 1; i <= 5001; i++) fac[i] = fac[i - 1] * i % 998244353;
  co[0][0] = 1;
  for (i = 1; i <= 5001; i++) {
    co[i][0] = 1;
    for (j = 1; j <= i; j++) {
      co[i][j] = (co[i - 1][j - 1] + co[i - 1][j]) % 998244353;
    }
  }
  ans = 1;
  for (i = 0; i <= min(a, b); i++) {
    tmp = (tmp + co[a][i] * co[b][i] % 998244353 * fac[i] % 998244353) %
          998244353;
  }
  ans = ans * tmp % 998244353, tmp = 0;
  for (i = 0; i <= min(a, c); i++) {
    tmp = (tmp + co[a][i] * co[c][i] % 998244353 * fac[i] % 998244353) %
          998244353;
  }
  ans = ans * tmp % 998244353, tmp = 0;
  for (i = 0; i <= min(c, b); i++) {
    tmp = (tmp + co[c][i] * co[b][i] % 998244353 * fac[i] % 998244353) %
          998244353;
  }
  ans = ans * tmp % 998244353;
  printf("%lld\n", ans);
}
