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