1 #include <iostream>
2 #include <cstring>
3 #include <string>
4 #include <vector>
5 #include <set>
6 #include <cstdio>
7 #include <algorithm>
8 using namespace std;
9 typedef long long LL;
10
11
12 struct Bign
13 {
14 static const int BASE=100000000;
15 static const int WIDTH=8;
16 vector<int>s;
17
18 Bign(LL n=0){*this=n;}
19 Bign(const string& str){*this=str;}
20 Bign operator =(LL n)
21 {
22 s.clear();
23 do
24 {
25 s.push_back(n%BASE);
26 n/=BASE;
27 }while(n>0);
28 return *this;
29 }
30 Bign operator =(const string& str)
31 {
32 s.clear();
33 int x,len=(str.length()-1)/WIDTH+1;
34 for(int i=0;i<len;i++)
35 {
36 int end=str.length()-i*WIDTH;
37 int start=max(0,end-WIDTH);
38 sscanf(str.substr(start,end-start).c_str(),"%d",&x);
39 s.push_back(x);
40 }
41 return *this;
42 }
43 Bign operator +(const Bign& b)const
44 {
45 int len1=s.size(),len2=b.s.size();
46 int len=max(len1,len2);
47 int ans=0;
48 Bign c;c.s.clear();
49 for(int i=0;i<len||ans!=0;i++)
50 {
51 if(i<len1) ans+=s[i];
52 if(i<len2) ans+=b.s[i];
53 c.s.push_back(ans%BASE);
54 ans/=BASE;
55 }
56 return c;
57 }
58 Bign operator -(const Bign& b)const
59 {
60
61 int len1=s.size(),len2=b.s.size();
62 Bign c;c.s.clear();
63 int ans=0,t=0;
64 for(int i=0;i<len1;i++)
65 {
66 if(i<len2) ans=s[i]-b.s[i]+t;
67 else ans=s[i]+t;
68 if(ans<0)
69 {
70 ans+=BASE;t=-1;
71 }
72 else t=0;
73 if(ans>0)c.s.push_back(ans);
74 }
75 return c;
76 }
77 Bign operator *(const Bign& b)const
78 {
79 Bign c;
80 int len1=s.size(),len2=b.s.size();
81 for(int i=0;i<len2;i++)
82 {
83 for(int j=0;j<len1;j++)
84 {
85 Bign ans=(LL)b.s[i]*s[j];
86 for(int k=0;k<i+j;k++)
87 ans.s.insert(ans.s.begin(),0);
88 c=c+ans;
89 }
90 }
91 return c;
92 }
93
94 bool operator <(const Bign& b)const
95 {
96 if(s.size()!=b.s.size()) return s.size()<b.s.size();
97 for(int i=s.size()-1;i>=0;i--)
98 if(s[i]!=b.s[i]) return s[i]<b.s[i];
99 return false;
100 }
101 bool operator ==(const Bign& b)const
102 {
103 if(s.size()!=b.s.size()) return false;
104 for(int i=s.size()-1;i>=0;i--)
105 if(s[i]!=b.s[i]) return false;
106 return true;
107 }
108 };
109 ostream& operator <<(ostream& out,const Bign& a)
110 {
111 out<<a.s.back();
112 char buf[10];
113 int len=a.s.size();
114 for(int i=len-2;i>=0;i--)
115 {
116 sprintf(buf,"%08d",a.s[i]);
117 out<<buf;
118 }
119 return out;
120 }
121 LL BtoL(const Bign& a)
122 {
123 LL c;
124 char buf[10];
125 string ss="";
126 int len=a.s.size();
127 sprintf(buf,"%d",a.s.back());ss+=(string)buf;
128 for(int i=len-2;i>=0;i--)
129 {
130 sprintf(buf,"%08d",a.s[i]);
131 ss+=(string)buf;
132 }
133 sscanf(ss.c_str(),"%lld",&c);
134 return c;
135 }
136 istream& operator >>(istream& in,Bign& a)
137 {
138 string s;
139 in>>s;
140 a=s;
141 return in;
142 }
