/*
    This code belongs to Aadit Ambadkar
    Date: 2021-06-13 05:08:53
*/
#include <bits/stdc++.h>
using namespace::std;

typedef long long ll;
#define F0R(i, n) for (int i = 0; i < n; i++)
#define R0F(i, n) for (int i = n-1; i >= 0; i--)
#define FOR(i, a, n) for (int i = a; i < n; i++)
#define pb push_back
#define fastio ios::sync_with_stdio(0); cin.tie(0)
#define FMOD 998244353
#define MOD 1000000007

int main() {
    fastio;
    int a, b, c; cin >> a >> b >> c;
    if (a==b) {
        cout << "=\n";
        return 0;
    }
    if (-a==b && c%2==0) {
        cout << "=\n";
        return 0;
    }
    if (a<=0 && b<=0) {
        if (c%2==0) {
            if (a<b) {
                cout << ">\n";
            } else {
                cout << "<\n";
            }
        } else {
            if (a<b) {
                cout << "<\n";
            } else {
                cout << ">\n";
            }
        }
    } else if (a<=0 && b>=0) {
        if (c%2==0) {
            if (-a<b) {
                cout << "<\n";
            } else {
                cout << ">\n";
            }
        } else {
            cout << "<\n";
        }
    } else if (a>=0 && b<=0) {
        if (c%2==0) {
            if (a<-b) {
                cout << "<\n";
            } else {
                cout << ">\n";
            }
        } else {
            cout << ">\n";
        }
    } else if (a>=0 && b>=0) {
        if (a<b) {
            cout << "<\n";
        } else {
            cout << ">\n";
        }
    }
}



#define _USE_MATH_DEFINES
//#include <bits/stdc++.h>
# include <iostream>
# include <array>
# include <string>
# include <vector>
# include <algorithm>
# include <functional>
# include <cmath>
# include <iomanip>
# include <stack>
# include <queue>
# include <numeric>
# include <map>
# include <set>
# include <unordered_map>
# include <unordered_set>
# include <chrono>
# include <random>
# include <bitset>
# include <cassert>
# include <climits>

template<typename T> inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); }
template<typename T> inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); }

#define rep2(i,t,n) for (int i = (t); i < (int)(n); i++)
#define rep(i,n) rep2(i,0,n)
#define YESNO(T) if(T){cout<<"YES"<<endl;}else{cout<<"NO"<<endl;}
#define yesno(T) if(T){cout<<"yes"<<endl;}else{cout<<"no"<<endl;}
#define YesNo(T) if(T){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}

using namespace std;
typedef long long ll;

int a,b,x,y;

int main() {
  cin >> a >> b >> x >> y;

  int diff = abs(a - b);

  int ans = 0;

  if(a > b) {
    diff--;
    ans += x;
  } else {
    ans += x;
  }

  rep(i,diff) {
    ans += 2 * x < y ? 2 * x : y;
  }

  cout << ans << endl;

  return 0;
}
