#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

const int MAX = 4000;
const int INF = INT_MAX / 2;

int main()
{
    int n, c, v;
    cin >> n >> c >> v;

    vector<vector<int> > dp(MAX, vector<int>(MAX, INF));
    dp[1][0] = 0;
    for(int i=0; i<MAX; ++i){
        for(int j=0; j<=i; ++j){
            dp[i][i] = min(dp[i][i], dp[i][j] + c);
            if(i + j < MAX)
                dp[i+j][j] = min(dp[i+j][j], dp[i][j] + v);
        }
    }

    int ans = INF;
    for(int i=0; i<=min(n,MAX-1); ++i){
        for(int j=1; j<=i; ++j){
            int len = n - i;
            ans = min(ans, dp[i][j] + (len + j - 1) / j * v);
        }
    }
    cout << ans << endl;

    return 0;
}