#include <bits/stdc++.h>
using namespace std;
long long int c[5002][5002];
long long int f[5002];
void calcNCR() {
  c[0][0] = 1;
  for (int i = 1; i < 5002; i++) {
    c[i][0] = 1;
    for (int j = 1; j < 5002; j++) {
      c[i][j] = (c[i - 1][j] + c[i - 1][j - 1]) % 998244353;
    }
  }
}
void calcFact() {
  f[0] = 1;
  for (int i = 1; i < 5002; i++) {
    f[i] = (f[i - 1] * i) % 998244353;
  }
}
long long int solve(int a, int b) {
  long long int sum = 0, cc;
  for (int i = 0; i <= min(a, b); i++) {
    cc = f[i];
    cc = (cc * c[a][i]) % 998244353;
    cc = (cc * c[b][i]) % 998244353;
    sum = (sum + cc) % 998244353;
  }
  return sum;
}
int main() {
  int a, b, c;
  scanf("%d%d%d", &a, &b, &c);
  calcNCR();
  calcFact();
  long long int sum = solve(a, b);
  sum = (sum * solve(b, c)) % 998244353;
  sum = (sum * solve(a, c)) % 998244353;
  printf("%lld\n", sum);
  return 0;
}
