import std.stdio, std.range, std.random, std.conv, std.string, std.math;
import std.algorithm.comparison, std.algorithm.iteration, std.algorithm.mutation, std.algorithm.searching, std.algorithm.sorting;

void main()
{
    long[] input = readln().strip.split().to!(long[]);
    long K = input[0];
    long A = input[1];
    long B = input[2];
    if(B-A<=2) { writeln(K+1);
    return; }
    
    long bis = 1 + K;
    long c = (K-(A-1))/2;
    writeln((B-A)*c+(bis-c*2) + (c==0?1:0));
}