using System;

namespace cs_ganri
{
	/// <summary>
	/// Class1 ‚ÌŠT—v‚Ì�à–¾‚Å‚·�B
	/// </summary>
	public class GanriHensai
	{
		/// <summary>
		/// ŒŽŠz•Ô�ÏŠz
		/// </summary>
		/// <param name="Ganpon">�Š—vŽ‘‹à</param>
		/// <param name="HensaiKaisu">•Ô�ωñ�”</param>
		/// <param name="Geturi">ŒŽ—˜</param>
		/// <returns>Œ³—˜�ž‚ÝŒŽŠz•Ô�ÏŠz</returns>
		public static int GetHensai(int Ganpon, int HensaiKaisu, double Geturi){
			//Excel‚ÌPMTŠÖ�”‚Æ“¯‚¶
			double theTemp;
			theTemp = (double)Ganpon * (Geturi / ((double)1 - (Math.Pow(((double)1 + Geturi),(double)HensaiKaisu))));
			return 0 - (int)theTemp;
		}

		public static int GetRisokuSum(int SouKaisu, int HensaiGaku, int Ganpon){
			return SouKaisu * HensaiGaku - Ganpon;
		}
		/// <summary>
		/// Žc�Šz‚ð•Ô‚·
		/// </summary>
		/// <param name="Ganpon">�Š—vŽ‘‹à</param>
		/// <param name="Hensai">Œ³—˜�ž‚ÝŒŽŠz•Ô�ÏŠz</param>
		/// <param name="Geturi">ŒŽ—˜</param>
		/// <param name="Kaisu">‰½‰ñ–Ú‚Ì•Ô�Ï</param>
		/// <returns>Žc�Šz‚ð•Ô‚·</returns>
		public static int GetZansai(int Ganpon, int Hensai, double Geturi, int Kaisu){
			double theTemp;
			theTemp = (Math.Pow(((double)1 + Geturi),(double)Kaisu) * ((double)Ganpon - (double)Hensai / Geturi) + (double)Hensai / Geturi);
			return Convert.ToInt32(theTemp);
		}

		/// <summary>
		/// ŒŽ•Ô�ÏŒ³‹àŠz‚ð•Ô‚·
		/// </summary>
		/// <param name="Ganpon">�Š—vŽ‘‹à</param>
		/// <param name="Hensai">ŒŽŠz•Ô�ÏŠz</param>
		/// <param name="Geturi">ŒŽ—˜</param>
		/// <param name="Kaisu">‰½‰ñ–ڂ̉ñ�”</param>
		/// <returns>ŒŽŠzŒ³‹à•Ô�ÏŠz‚ð•Ô‚·</returns>
		public static int GetGankin(int Ganpon, int Hensai, double Geturi, int Kaisu){
			//Žx•¥‚¢‘O‚ÌŽc�Â�|Žx•¥‚¢Œã‚ÌŽc�Â
			int theGankin;
			if(Kaisu > 1){
				theGankin = GetZansai(Ganpon,Hensai,Geturi,Kaisu - 1) 
					- GetZansai(Ganpon,Hensai,Geturi,Kaisu);
			}else{
				theGankin = Ganpon - GetZansai(Ganpon,Hensai,Geturi,Kaisu);
			}
			return theGankin;
		}

		/// <summary>
		/// ŒŽŠz—˜‘§‚ð•Ô‚·
		/// </summary>
		/// <param name="Hensai">ŒŽŠzŒ³—˜�ž‚Ý•Ô�ÏŠz</param>
		/// <param name="Gankin">ŒŽŠzŒ³‹àŠz</param>
		/// <returns>ŒŽŠz—˜‘§Šz‚ð•Ô‚·</returns>
		public static int GetRisoku(int TukiHensai, int Gankin){
			return TukiHensai - Gankin;
		}
	}
}