Submission #994098

---

Source Code Expand

using System;
using System.Text;
using System.Collections.Generic;
class Solve{
    long N,A;
    public Solve(){}
    StringBuilder sb;
    public static int Main(){
        new Solve().Run();
        return 0;
    }
    void Run(){
        sb = new StringBuilder();
        Read();
        Calc();
        Console.Write(sb.ToString());
    }
    void Calc(){
        int d = 1;
        long min = N;
        {   
            long i = 1;
            while(i <= N){
                d++;
                i *= 2;
            }
        }
        for(int i=0;i<d;i++){
            long f = 0;
            long l = N-1;
            while(f != l){
                long c = (f+l)/2;
                long a = Pow(c,i+1);
                if(a == -1 || a > N){
                    l = c;
                }
                else{
                    f = c+1;
                }
            }
            long b = -1;
            long t = Pow(f,i+1);
            while(t >= N){
                t /= f;
                t *= f-1;
                b++;
            }
            if(min > f*(i+1)-b+A*i){
                min = f*(i+1)-b+A*i;
            }
        }
        sb.Append(min+"\n");
    }
    long Pow(long i,long j){
        if(j == 0){
            return 1;
        }
        else if(j % 2 == 0){
            long k = Pow(i,j/2);
            if(k == -1 || k > 1000000){
                return -1;
            }
            else{
                return k*k;
            }
        }
        else{
            long k = Pow(i,j-1);
            if(k == -1 || k*i > 1000000000000){
                return -1;
            }
            else{
                return k*i;
            }
        }
    }
    void Read(){
        string[] str = Console.ReadLine().Split(' ');
        N = Int64.Parse(str[0]);
        A = Int64.Parse(str[1]);
    }    
}

Submission Info

Judge Result