#include <bits/stdc++.h>
using namespace std;
#define rep(i, c) for (int i = 0; i < (int)c; i++)
using ll = long long;
const ll mod = 998244353;
ll func(ll n) { return (n * (n + 1) / 2) % mod; }
int main() {
    ll A, B, C;
    cin >> A >> B >> C;
    ll ans = ((func(A) * func(B)) % mod) * func(C);
    cout << ans % mod << "\n";
    return 0;
}
#include <bits/stdc++.h>
using namespace std;
#define FastIO ios_base::sync_with_stdio(false),cin.tie(NULL);
#define endl "\n"
#define rep(i,a,b) for(int i=a;i<=b;i++)
#define irep(i,a,b) for(int i=a;i>=b;i--)
#define ip(V,n) vector<float> V(n); for(int _i=0;_i<n;_i++) cin>>V[_i]
#define op(V,sep) for(int _i=0;_i<V.size();_i++) cout<<V[_i]<<sep
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define pii pair<int,int>
#define mp make_pair
#define fi first
#define se second
#define int long long int
#define MOD 998244353
#define MAX 100005
#define INF 1e18
//.............. User: zero_bug   (Not to touch) ....................

void solve() {
    int a,b,c;
    cin>>a>>b>>c;
    int ans=1;
    ans=((a*(a+1))/2)%MOD;
    ans=ans*(((b*(b+1))/2)%MOD);
    ans%=MOD;
    ans=ans*(((c*(c+1))/2)%MOD);
    cout<<(ans%MOD)<<endl;
}

int32_t main() {
    FastIO
    // int t;
    // cin>>t;
    // rep(tt,1,t) {
    //     cout<<"Case #"<<tt<<":"<<" ";
        solve();
    // }
}