#include<iostream>
#include<bits/stdc++.h>
#define m_p make_pair
#define fi first
#define se second
#define pb push_back
typedef long long ll;
#define f(i,n) for(ll i=0;i<n;i++)
#define f1(i,n) for(ll i=1;i<=n;i++)
#define   crap ios_base::sync_with_stdio(0); cin.tie(0);cout.tie(0)
using namespace std;
#define INF 1000000
#define vll vector<ll>
const int M = 1e9+7;
ll fastpower(ll x,ll n,ll M)
{
    if(n==0)
        return 1;
    else if(n%2 == 0)        //n is even
        return fastpower((x*x)%M,n/2,M);
    else                             //n is odd
        return (x*fastpower((x*x)%M,(n-1)/2,M))%M;
}
ll GCD(ll A, ll B) {
    if(B==0)
        return A;
    else
        return GCD(B, A % B);
}
bool vowl(char c)
{
  return c=='a'||c=='e'||c=='i'||c=='o'||c=='u';
}
ll modInverse(ll A,ll M)// when M is prime
{
    return fastpower(A,M-2,M);
}
void sieve(ll N) {
        bool isPrime[N+1];
        for(ll i = 0; i <= N;++i) {
            isPrime[i] = true;
        }
        isPrime[0] = false;
        isPrime[1] = false;
        for(ll i = 2; i * i <= N; ++i) {
             if(isPrime[i] == true) {                    //Mark all the multiples of i as composite numbers
                 for(ll j = i * i; j <= N ;j += i)
                     isPrime[j] = false;
            }
        }
    }
vector<ll> factorize(ll n) {
    vector<ll> res;
    for (ll i = 2; i * i <= n; ++i) {
        while (n % i == 0) {
            res.push_back(i);
            n /= i;
        }
    }
    if (n != 1) {
        res.push_back(n);
    }
    return res;
}
 
int main()
{
  crap;
  #ifndef ONLINE_JUDGE
      freopen("input.txt","r",stdin);
      freopen("output.txt","w",stdout);
      #endif
           double a,b,p,q;
           cin>>a>>b>>p>>q;
           cout<<setprecision(12)<<(b*p+q*a)/(q+b)<<endl;
  return 0;
}
#include <bits/stdc++.h>
using namespace std;

#define pb push_back

#define int ll
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;
using vpii = vector<pii>;
using vvpii = vector<vpii>;

template<typename T, typename U>
ostream& operator<<(ostream& o, const pair<T,U>& p) {
  return o << "(" << p.first << "," << p.second << ")";
}

template<typename T, typename U>
ostream& operator<<(ostream& o, const map<T,U>& m) {
  o << "{";
  for (const pair<T,U>& p : m)
    o << p.first << ": " << p.second << ",";
  return o << "}";
}

template<typename T>
ostream& operator<<(ostream& o, const vector<T>& v) {
  o << "[";
  for (const T& x : v)
    o << x << ",";
  return o << "]";
}

template<typename T>
ostream& operator<<(ostream& o, const vector<vector<T>>& v) {
  o << "[";
  for (const vector<T>& x : v)
    o << x << ",\n";
  return o << "]";
}

constexpr int MOD = 998244353;


signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

    int a, b, c;
    cin >> a >> b >> c;

    int sumc = (c+1)*c/2 % MOD;
    int sumb = (b+1)*b/2 % MOD;
    int suma = (a+1)*a/2 % MOD;
    int res = suma * sumb % MOD * sumc % MOD;
    cout << res << "\n";
}
