高精度模板

C++类，可以进行正整数之间的加减乘除，模，大小比较。输入输出用cin，cout；

  1 #include <stdio.h>
  2 #include <iostream>
  3 #include <cstdio>
  4 #include <cstdlib>
  5 #include <cstring>
  6 #include <string>
  7 #include <algorithm>
  8 using namespace std;
  9 
 10 const int MAXN = 410;
 11 
 12 struct bign
 13 {
 14     int len, s[MAXN];
 15     bign ()
 16     {
 17         memset(s, 0, sizeof(s));
 18         len = 1;
 19     }
 20     bign (int num) { *this = num; }
 21     bign (const char *num) { *this = num; }
 22     bign operator = (const int num)
 23     {
 24         char s[MAXN];
 25         sprintf(s, "%d", num);
 26         *this = s;
 27         return *this;
 28     }
 29     bign operator = (const char *num)
 30     {
 31         for(int i = 0; num[i] == '0'; num++) ;  //去前导0
 32         len = strlen(num);
 33         for(int i = 0; i < len; i++) s[i] = num[len-i-1] - '0';
 34         return *this;
 35     }
 36     bign operator + (const bign &b) const //+
 37     {
 38         bign c;
 39         c.len = 0;
 40         for(int i = 0, g = 0; g || i < max(len, b.len); i++)
 41         {
 42             int x = g;
 43             if(i < len) x += s[i];
 44             if(i < b.len) x += b.s[i];
 45             c.s[c.len++] = x % 10;
 46             g = x / 10;
 47         }
 48         return c;
 49     }
 50     void clean()
 51     {
 52         while(len > 1 && !s[len-1]) len--;
 53     }
 54     bign operator * (const bign &b) //*
 55     {
 56         bign c;
 57         c.len = len + b.len;
 58         for(int i = 0; i < len; i++)
 59         {
 60             for(int j = 0; j < b.len; j++)
 61             {
 62                 c.s[i+j] += s[i] * b.s[j];
 63             }
 64         }
 65         for(int i = 0; i < c.len; i++)
 66         {
 67             c.s[i+1] += c.s[i]/10;
 68             c.s[i] %= 10;
 69         }
 70         c.clean();
 71         return c;
 72     }
 73     bign operator - (const bign &b)
 74     {
 75         bign c;
 76         c.len = 0;
 77         for(int i = 0, g = 0; i < len; i++)
 78         {
 79             int x = s[i] - g;
 80             if(i < b.len) x -= b.s[i];
 81             if(x >= 0) g = 0;
 82             else
 83             {
 84                 g = 1;
 85                 x += 10;
 86             }
 87             c.s[c.len++] = x;
 88         }
 89         c.clean();
 90         return c;
 91     }
 92     bign operator / (const bign &b)
 93     {
 94         bign c, f = 0;
 95         for(int i = len-1; i >= 0; i--)
 96         {
 97             f = f*10;
 98             f.s[0] = s[i];
 99             while(f >= b)
100             {
101                 f -= b;
102                 c.s[i]++;
103             }
104         }
105         c.len = len;
106         c.clean();
107         return c;
108     }
109     bign operator % (const bign &b)
110     {
111         bign r = *this / b;
112         r = *this - r*b;
113         return r;
114     }
115     bool operator < (const bign &b)
116     {
117         if(len != b.len) return len < b.len;
118         for(int i = len-1; i >= 0; i--)
119         {
120             if(s[i] != b.s[i]) return s[i] < b.s[i];
121         }
122         return false;
123     }
124     bool operator > (const bign &b)
125     {
126         if(len != b.len) return len > b.len;
127         for(int i = len-1; i >= 0; i--)
128         {
129             if(s[i] != b.s[i]) return s[i] > b.s[i];
130         }
131         return false;
132     }
133     bool operator == (const bign &b)
134     {
135         return !(*this > b) && !(*this < b);
136     }
137     bool operator != (const bign &b)
138     {
139         return !(*this == b);
140     }
141     bool operator <= (const bign &b)
142     {
143         return *this < b || *this == b;
144     }
145     bool operator >= (const bign &b)
146     {
147         return *this > b || *this == b;
148     }
149     string str() const
150     {
151         string res = "";
152         for(int i = 0; i < len; i++) res = char(s[i]+'0') + res;
153         return res;
154     }
155 };
156 
157 istream& operator >> (istream &in, bign &x)
158 {
159     string s;
160     in >> s;
161     x = s.c_str();
162     return in;
163 }
164 
165 ostream& operator << (ostream &out, const bign &x)
166 {
167     out << x.str();
168     return out;
169 }

View Code

JAVA BigInteger类。

函数:

valueOf(parament); 将参数转换为制定的类型

比如 int a=3;

BigInteger b=BigInteger.valueOf(a);

则b=3;

String s=”12345”;

BigInteger c=BigInteger.valueOf(s);

则c=12345；

add();　　subtract();　　multiply();　　divide();　　pow();

gcd();　　abs();　　mod();　　max();　　min();　　equals();

 1 import java.math.BigInteger;
 2 import java.util.Scanner;
 3 public class Main {
 4 
 5     public static void main(String[] args) {
 6         // TODO Auto-generated method stub
 7         BigInteger a,b,c;
 8         Scanner cin=new Scanner(System.in);
 9         while(cin.hasNext())
10         {
11             a=cin.nextBigInteger();
12             b=cin.nextBigInteger();
13             c=a.max(b);
14             System.out.println(c);
15         }
16     }
17 
18 }

View Code

参考文章：http://blog.csdn.net/wall_f/article/details/8373395

　　　　　http://blog.sina.com.cn/s/blog_622bd1660100oqpv.html

posted @ 2016-04-25 15:53 L&King 阅读(229) 评论(0) 收藏举报

刷新页面返回顶部