#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll mod=998244353;
ll power(ll x, ll y)
{
    ll res = 1;     // Initialize result

     // Update x if it is more than or
                // equal to p

    //if (x == 0) return 0; // In case x is divisible by p;

    while (y > 0)
    {
        // If y is odd, multiply x with result
        if (y & 1)
            res = (res*x) % mod;

        // y must be even now
        y = y>>1; // y = y/2
        x = (x*x) % mod;
    }
    return res;
}
int main()
{
    ll a,b,c;
    cin>>a>>b>>c;
    ll ans;
    ans=(a*(a+1));
    ans=ans%mod;
    ans=((ans%mod)*((b*(b+1))%mod))%mod;
    ans=ans%mod;
    ans=((ans%mod)*((c*(c+1))%mod))%mod;
    ans=ans%mod;
    ll temp=power(8,mod-2);
    ans=(((ans)%mod)*(temp%mod))%mod;
    cout<<ans<<endl;

}

#include<bits/stdc++.h>
using namespace std;
# define test int t;cin>>t;while(t--)
#define ff first
#define ss second
#define ll long long int
#define pb push_back
#define pii pair< int,int >
#define fast ios::sync_with_stdio(0) , cin.tie(0) , cout.tie(0) ;

int main(){
    ll a,b,c;
    cin>>a>>b>>c;
    ll mod = 998244353;
    ll ans  = (((a) * (a + 1) / 2) % mod);
 
    ans = (ans * (((b) * (b + 1) / 2) % mod)) % mod;
 
    ans = (ans * (((c) * (c + 1) / 2) % mod)) % mod;
 
    cout << ans << endl;
}