console.log((args=>{
  const [K,A,B] = args.trim().split(' ').map(v=>v|0);
  if ( B <= A + 2 || K < A ) return `${1+K}`;
  const d = BigInt(B-A);
  const c = BigInt(K-A+1>>1)-1n;
  const l = BigInt(!(K-A&1)+B);
  return `${d * c + l}`;
})(require('fs').readFileSync('/dev/stdin', 'utf8')));
