/*
TASK:notalike
LANG:C++
*/
#include <iostream>

using namespace std;

int n, p, q;
int start;

void game (int br, int prev, bool pl)
          {
               int i;
               bool fl=false;
               
               for (i=q; i>=p; i--)
                   if (i<=br) if (i!=prev)
                                 {
                                          fl=true;
                                          game(br-i,i,!pl);
                                 }
               
               if (!fl) if (pl) { printf("%d\n", start ); exit(0); }
         }

int main()
{
    scanf("%d%d%d", &n, &p, &q);
    
    for (start=q; start>=p; start--)
        if(start<=n) game(n-start,start,1);
    
    printf("0\n");
    
return 0;
}

