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1 #include<cstdio> 2 #include<cstring> 3 #include<vector> 4 #include<iostream> 5 using namespace std; 6 struct Big { 7 static const int BASE = 100000000; // change 8 static const int WIDTH = 8; // change 9 /* 10 WIDTH可随需求不同而变动： 11 ①：没有乘除mod时，WIDTH为8时效率最高，在8以上可能出错。 12 ②：WIDTH增大时，加减乘都会变快，但除和mod会变慢，所以没有除和mod时，尽量把WIDTH开大，有乘法时最大为4。 13 ③：如果乘数都很小像2,3,4之类的数，WIDTH也可以开到8。 14 ④：如果运算符要求很全，那么WIDTH为3比较合适。 15 如果要改WIDTH的话，需要改三处地方，已在代码中标记上“change”。 16 */ 17 vector<int> s; 18 Big(long long num = 0){*this=num;} 19 Big operator = (long long num) { 20 s.clear(); 21 do { 22 s.push_back(num%BASE); 23 num/=BASE; 24 }while(num>0); 25 return *this; 26 } 27 Big operator = (const string& str) { 28 s.clear(); 29 int x,len=(str.length()-1)/WIDTH+1; 30 for(int i=0;i<len;i++) { 31 int end=str.length()-i*WIDTH; 32 int start=max(0,end-WIDTH); 33 sscanf(str.substr(start,end-start).c_str(),"%d",&x); 34 s.push_back(x); 35 } 36 return *this; 37 } 38 Big operator + (const Big& b) const { 39 Big c; 40 c.s.clear(); 41 for(int i=0,g =0;;i++) { 42 if(g==0&&i>=s.size()&&i>=b.s.size()) break; 43 int x=g; 44 if(i<s.size()) x+=s[i]; 45 if(i<b.s.size()) x+=b.s[i]; 46 c.s.push_back(x%BASE); 47 g=x/BASE; 48 } 49 return c; 50 } 51 Big operator - (const Big& b) const { 52 Big c; 53 c.s.clear(); 54 int i,g,n=s.size(),m=b.s.size(); 55 for(i=0,g=0;i<n;i++) { 56 int x=s[i]-g; 57 if(i<m) x-=b.s[i]; 58 if(x>=0) g=0; 59 else { 60 g=1; 61 x+=BASE; 62 } 63 c.s.push_back(x); 64 } 65 i=c.s.size()-1; 66 while(c.s[i]==0&&i) c.s.pop_back(),i--; 67 return c; 68 } 69 Big operator * (const Big &b) const { 70 Big c; 71 int i,j,n=s.size(),m=b.s.size(),size=m+n; 72 c.s.resize(size,0); 73 for(i=0;i<n;i++) 74 for(j=0;j<m;j++) 75 c.s[i+j] += s[i] * b.s[j]; 76 for(i=0;i<size;i++) { 77 c.s[i+1]+=c.s[i]/BASE; 78 c.s[i]%=BASE; 79 } 80 i=size-1; 81 while(c.s[i]==0&&i) c.s.pop_back(),i--; 82 return c; 83 } 84 Big operator / (const Big& b) const { 85 Big c,f=0; 86 int n=s.size(),i; 87 c.s.resize(n,0); 88 for(i=n-1;i>=0;i--) { 89 f=f*BASE; 90 f.s[0]=s[i]; 91 while(f>=b) { 92 f-=b; 93 c.s[i]++; 94 } 95 } 96 i=n-1; 97 while(c.s[i]==0&&i) c.s.pop_back(),i--; 98 return c; 99 } 100 Big operator % (const Big &b) const { 101 Big r=*this/b; 102 r=*this-r*b; 103 return r; 104 } 105 106 Big operator += (const Big& b){*this=*this+b;return *this;} 107 Big operator -= (const Big& b){*this=*this-b;return *this;} 108 Big operator *= (const Big& b){*this=*this*b;return *this;} 109 Big operator /= (const Big& b){*this=*this/b;return *this;} 110 Big operator %= (const Big& b){*this=*this%b;return *this;} 111 112 bool operator < (const Big& b) const { 113 int n=s.size(),m=b.s.size(); 114 if(m>n) return 1; 115 if(m<n) return 0; 116 for(int i=s.size()-1;i>=0;i--) { 117 if(s[i]<b.s[i]) return 1; 118 if(s[i]>b.s[i]) return 0; 119 } 120 return 0; 121 } 122 bool operator > (const Big& b) const {return b<*this;} 123 bool operator >= (const Big& b) const {return !(*this<b);} 124 bool operator <= (const Big& b) const {return !(b<*this);} 125 bool operator == (const Big& b) const {return !(*this<b)&&!(b<*this);} 126 bool operator != (const Big& b) const {return (*this<b)||(b<*this);} 127 }; 128 129 ostream& operator << (ostream &out, const Big& x) { 130 out<<x.s.back(); 131 for(int i=x.s.size()-2;i>=0;i--) { 132 char buf[10]; 133 sprintf(buf,"%08d",x.s[i]); // change 134 for(int j=0;j<strlen(buf);j++) out<<buf[j]; 135 } 136 return out; 137 } 138 istream& operator >> (istream &in,Big& x) { 139 string s; 140 if(!(in>>s)) return in; 141 x=s; 142 return in; 143 } 144 int main() { 145 ios_base::sync_with_stdio(0); // 关闭流同步可以变快些 146 Big a,b; 147 cin>>a>>b; 148 cout<<a<<endl; 149 cout<<b<<endl; 150 cout<<a+b<<endl; 151 cout<<a-b<<endl; 152 cout<<a*b<<endl; 153 cout<<a/b<<endl; 154 cout<<a%b<<endl; 155 if(a<b) cout<<"Yes"<<endl; 156 else cout<<"No"<<endl; 157 return 0; 158 }