Submission #23316679

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Source Code Expand

#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<ll> vl;
typedef pair<ll, ll> pl;
typedef priority_queue<ll> PQ;
typedef priority_queue<ll, vector<ll>, greater<>> PQR;
struct edge {ll to;ll id;edge(ll t,ll i):to(t),id(i){}};
typedef vector<vector<ll> > Graph;
typedef vector<vector<edge> > WGraph;
#define rep(i, n) for(ll i = 0; (i) < ll(n); (i)++)
#define all(v) (v).begin(), (v).end()
#define pb emplace_back
#define V vector
#define uniquify(vec) (vec).erase(std::unique((vec).begin(), (vec).end()), (vec).end())
constexpr ll MOD1 = 1e9 + 7;
constexpr ll MOD9 =  998244353;
constexpr ll INF = MOD1*MOD1+1;
ll mod(ll n, ll m){if(n >= 0) {return n % m;} else return (n%m + m)%m;}
ll div_ceil(ll a, ll b){return (a + b - 1) / b;}
template<typename T> T pw(T x,ll n) {T ret=1;while(n>0){if(n&1)ret=ret*x;x=x*x;n>>=1;}return ret;}
template<typename T> void rsort(vector<T> &v) {sort(all(v), greater<T>());}
template<typename T> bool chmax(T &a,const T& b) {if(a<b){a=b;return true;}return false;}
template<typename T> bool chmin(T &a,const T& b) {if(a>b){a=b;return true;}return false;}
template<typename T> void fin(const T &a) {cout << a << '\n';exit(0);}
template<typename T, typename S> pair<T, S> mp(const T &a, const S &b){return make_pair(a, b);}
template<typename T, typename S>
std::ostream &operator<<(std::ostream& os, const pair<T, S> &p){
    os << "(" << p.first << ", " << p.second << ")";
    return os;
}
template <typename T>
std::ostream &operator<<(std::ostream& os, const vector<T> &v){
    int n = v.size();
    os << "[";
    for(int i = 0; i < n; i++){
        if(i == n - 1) os << v[i];
        else os << v[i] << ", ";
    }
    os << "]";
    return os;
}
template <typename T, typename S>
std::ostream &operator<<(std::ostream& os, const map<T, S> &mp){
    for(auto iter = mp.begin(); iter != mp.end(); iter++){
        os << "(" << iter->first << ", " << iter->second << ")" << " ";
    }
    return os;
}
template <typename T>
std::ostream &operator<<(std::ostream& os, const set<T> &s){
    os << "{";
    for(auto c : s) os << c << " ";
    os << "}";
    return os;
}
//#define LOCAL
#ifdef LOCAL
#define dump(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl
#else
#define dump(x) true
#endif

using mint = modint1000000007;
//using mint = modint998244353;


int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << std::fixed << std::setprecision(15);

    ll R_, B_, x_, y_;
    __int128 R, B, x, y; cin >> R_ >> B_ >> x_ >> y_;
    R = R_;
    B = B_;
    x = x_;
    y = y_;
    if(x == 1 || y == 1){
        cout << ll(min(R, B)) << '\n';
        exit(0);
    }
    if(B * x < R){
        cout << ll(B) << '\n';
        exit(0);
    } else if(R * y < B){
        cout << ll(R) << '\n';
        exit(0);
    }
    __int128 ub = (R * (y - 1) + B * (x - 1)) / (x * y - 1);
    __int128 l = (ub * y - B + y - 1 - 1) / (y - 1);
    __int128 u = (R - ub) / (x - 1);
    if(ub <= 0){
        fin(0);
    }
    if(u >= l && ub * y / (y - 1) >= l){
        cout << ll(ub) << '\n';
    } else {
        cout << ll(ub) - 1 << '\n';
    }

    return 0;
}

Submission Info

Judge Result