function main(input) {
    const args = input.split(/\n|\s/)
    const K = parseInt(args[0],10)
    const A = parseInt(args[1],10)
    const B = parseInt(args[2],10)
    const C = B-A
    const k = (K-A+1).toFixed(0)
    const g = (k%2).toFixed(0)
    
    if(C<=2 || K<=A){
      var c = (K+1).toFixed(0)
      console.log(c)
    }else if(g==0){
      var f = (k/2).toFixed(0)
      f = (f*C).toFixed(0)
      console.log(f)
    }else{
      var f = (k-1).toFixed(0)
      f = (f/2).toFixed(0)
      f = (C*f).toFixed(0) 
      f = (f+1).toFixed(0)
      console.log(f)
    } 
    
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));