[백준] 1712번 : 손익분기점 - C#

https://www.acmicpc.net/problem/1712

using System;

class Program
{
    static void Main() {
        string[] s=Console.ReadLine().Split(' ');
        int a=int.Parse(s[0]);
        int b=int.Parse(s[1]);
        int c=int.Parse(s[2]);
        int n=c-b;
        
        if(n<=0) Console.Write(-1);
        else Console.Write(a/n+1);
    }
}