#include<bits/stdc++.h>
using namespace std;
using ll=long long int;
#define mod 998244353
 
int main()
{
  ll a,b,c;
  cin>>a>>b>>c;
  
  ll sum1 = ((a*(a+1))/2);
  
  ll sum2=  ((b*(b+1))/2);
  
  ll sum3=  ((c*(c+1))/2); 
  
  cout<<(((sum1%mod)*(sum2%mod))%mod*(sum3%mod))%mod;
}
#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
typedef vector<ll> vl;
typedef vector<bool> vb;
typedef vector<string> vs;
typedef vector<char> vc;
typedef queue<ll> ql;
typedef deque<ll> dql;
typedef priority_queue<ll> pql;
typedef set<ll> sl;
typedef pair<ll, ll> pl;
typedef vector<vl> vvl;
typedef vector<pl> vpl;
#define rep(i, n) for(ll i = 0; i < ll(n); i++)
#define rep2(i, k, n) for(ll i = ll(k); i <= ll(n); i++)
#define rep3(i, n, k) for(ll i = ll(n); i >= ll(k); i--)
#define all(v) (v).begin(), (v).end()
ll mod(ll a, ll b) {if(b == 0) return 0; return (a % b + b) % b;}
bool chmin(ll &a, ll b) {if(b < a) {a = b; return 1;} return 0;}
bool chmax(ll &a, ll b) {if(b > a) {a = b; return 1;} return 0;}
const ll INF = 1LL << 60;
//const ll MOD = 1e9 + 7;
const ll MOD = 998244353;
const ll MAX = 2e5;
const ld eps = 1e-9;
const char newl = '\n';

ll Triangular_Number(ll n) {return ((n*(n+1))/2)%MOD;}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);

  ll a, b, c;
  cin >> a >> b >> c;
  cout << ((Triangular_Number(a) * Triangular_Number(b) % MOD) * Triangular_Number(c)) % MOD << newl;
  return 0;
}