无穷大加法.上万位数相加

 

using System;
using System.Collections.Generic;
using System.Text;

namespace temp
{
    class Program
    {
        static void Main(string[] args)
        {
            string a = BigAddition("2545123654125874589656584552565468","3214569874566985521455688758966522322145587");
            
        }

        private static string BigAddition(string numberA, string numberB)
        {
            int groupTerm = 4;//默认4位
            List<string> jieguo = GetresultList(numberA, numberB, groupTerm);
            string ResultString = "";
            for (int i = 0; i < jieguo.Count; i++)
            {
                ResultString += jieguo[jieguo.Count-1 - i];
            }
            return ResultString;
        }

        private static List<string> GetresultList(string numberA, string numberB, int groupTerm)
        {
            string[] numberAlist = listisok(numberA, groupTerm);
            string[] numberBlist = listisok(numberB, groupTerm);
            List<string> jieguo = jisuan(numberAlist, numberBlist);
            List<string> zuihoujieguoji = new List<string>();
            for (int i = 0; i < jieguo.Count; i++)
            {
                if (int.Parse(jieguo[i].ToString()) > groupTerm)
                {
                    string fanzhunjieguo = Fanzhuan(jieguo[i].ToString());
                    string jieguo1;
                    string shengyujieguo = "0";
                    if (fanzhunjieguo.Length < groupTerm)
                    {
                        jieguo1 = Fanzhuan(fanzhunjieguo.Substring(0));
                    }
                    else
                    {
                        jieguo1 = Fanzhuan(fanzhunjieguo.Substring(0, groupTerm));
                        shengyujieguo = Fanzhuan(fanzhunjieguo.Substring(groupTerm));
                        if (shengyujieguo != null || shengyujieguo == "0")
                        {
                            jieguo[i + 1] = (int.Parse(jieguo[i + 1]) + int.Parse(shengyujieguo)).ToString();
                        }
                    }

                    zuihoujieguoji.Add(jieguo1);
                }
            }
            return zuihoujieguoji;
        }

 


        //计算结果
        private static List<string> jisuan(string[] numberAlist, string[] numberBlist)
        {
            List<string> jieguo = new List<string>();
            if (numberAlist.Length > numberBlist.Length)
            {
                for (int i = 0; i < numberAlist.Length; i++)
                {
                    if (i > numberBlist.Length - 1)
                    {
                        jieguo.Add(numberAlist[i].ToString());
                    }
                    else
                    {
                        int temp = int.Parse(numberAlist[i].ToString()) + int.Parse(numberBlist[i].ToString());
                        jieguo.Add(temp.ToString());
                    }
                }

            }
            else
            {
                for (int i = 0; i < numberBlist.Length; i++)
                {
                    if (i > numberAlist.Length - 1)
                    {
                        jieguo.Add(numberBlist[i].ToString());
                    }
                    else
                    {
                        int temp = int.Parse(numberAlist[i].ToString()) + int.Parse(numberBlist[i].ToString());
                        jieguo.Add(temp.ToString());
                    }
                }

            }
            return jieguo;
        }

        private static string[] listisok(string numberA, int groupTerm)
        {
            string[] numberAlist = getnewlist(numberA, groupTerm);
            int numberAgroup = group(numberA, groupTerm);
            for (int i = 0; i < numberAlist.Length; i++)
            {
                numberAlist[i] = Fanzhuan(numberAlist[i].ToString());
            }
            return numberAlist;
        }

        private static string[] getnewlist(string number, int groupTerm)
        {
            //根据条件分组
            int numberAgroup = group(number, groupTerm);//数字A分组个数
            string[] grouplist = new string[numberAgroup];
            //字符串反转
            string lingshistring = Fanzhuan(number);
            for (int i = 0; i < numberAgroup; i++)
            {
                if (i < numberAgroup - 1)
                    grouplist[i] = (lingshistring.Substring(i * groupTerm, groupTerm));
                else grouplist[i] = lingshistring.Substring(i * groupTerm);
            }
            return grouplist;
        }

        private static string Fanzhuan(string number)
        {
            char[] fanzhuanzhunbei = number.ToCharArray();
            Array.Reverse(fanzhuanzhunbei);//反转
            string lingshistring = null;
            for (int i = 0; i < fanzhuanzhunbei.Length; i++)
            {
                lingshistring += fanzhuanzhunbei[i];
            }
            return lingshistring;
        }

        private static int group(string number, int groupTerm) //对数字分组判断
        {
            int numbergroup;
            if (number.Length % groupTerm == 0)
            {
                numbergroup = number.Length / groupTerm;
            }
            else numbergroup = number.Length / groupTerm + 1;
            return numbergroup;
        }
    }
}

搞了2个小时.. 出来了.. 代码还能在优化.. 我只做出了结果.保证结果正确,还可以做乘法运算

例如

2545123654125874589656584552565468+
3214569874566985521455688758966522322145587=
3214569877112109175581563348623106874711055

2.

23521456856954789999559559523221112244558411222541225442222556688445852+

2544114556698778895545566321445877899654552333655211144455777855522111=

26065571413653568895105125844666990144212963556196436586678334543967963