#include<bits/stdc++.h> using namespace std; const int maxn=10005;/*精度位数,自行调整*/ //1.如果需要控制输出位数的话，在str()里面把len调成需要的位数 //2.很大的位数是会re的，所以如果是幂运算的话，如 计算x^p的位数n, n=p*log(10)x+1;(注意要加一） //3.还可以加上qmul，取模的过程也就是str()，c_str()再搞一次 class bign { //io*2 bign*5*2 bool*6 friend istream& operator>>(istream&,bign&); friend ostream& operator<<(ostream&,const bign&); friend bign operator+(const bign&,const bign&); friend bign operator+(const bign&,int&); friend bign operator*(const bign&,const bign&); friend bign operator*(const bign&,int&); friend bign operator-(const bign&,const bign&); friend bign operator-(const bign&,int&); friend bign operator/(const bign&,const bign&); friend bign operator/(const bign&,int&); friend bign operator%(const bign&,const bign&); friend bign operator%(const bign&,int&); friend bool operator<(const bign&,const bign&); friend bool operator>(const bign&,const bign&); friend bool operator<=(const bign&,const bign&); friend bool operator>=(const bign&,const bign&); friend bool operator==(const bign&,const bign&); friend bool operator!=(const bign&,const bign&); private://如果想访问len,改成public int len,s[maxn]; public: bign() { memset(s,0,sizeof(s)); len=1; } bign operator=(const char* num) { int i=0,ol; ol=len=strlen(num); while(num[i++]=='0'&&len>1) len--; memset(s,0,sizeof(s)); for(i=0; i<len; i++) s[i]=num[ol-i-1]-'0'; return *this; } bign operator=(int num) { char s[maxn]; sprintf(s,"%d",num); *this=s; return *this; } bign(int num) { *this=num; } bign(const char* num) { *this=num; } string str() const { string res=""; for(int i=0; i<len; i++) res=char(s[i]+'0')+res; if(res=="") res="0"; return res; } }; bool operator<(const bign& a,const bign& b) { int i; if(a.len!=b.len) return a.len<b.len; for(i=a.len-1; i>=0; i--) if(a.s[i]!=b.s[i]) return a.s[i]<b.s[i]; return false; } bool operator>(const bign& a,const bign& b) { return b<a; } bool operator<=(const bign& a,const bign& b) { return !(a>b); } bool operator>=(const bign& a,const bign& b) { return !(a<b); } bool operator!=(const bign& a,const bign& b) { return a<b||a>b; } bool operator==(const bign& a,const bign& b) { return !(a<b||a>b); } bign operator+(const bign& a,const bign& b) { int up=max(a.len,b.len); bign sum; sum.len=0; for(int i=0,t=0;t||i<up; i++) { if(i<a.len) t+=a.s[i]; if(i<b.len) t+=b.s[i]; sum.s[sum.len++]=t%10; t/=10; } return sum; } bign operator+(const bign& a,int& b) { bign c=b; return a+c; } bign operator*(const bign& a,const bign& b) { bign res; for(int i=0; i<a.len; i++) { for(int j=0; j<b.len; j++) { res.s[i+j]+=(a.s[i]*b.s[j]); res.s[i+j+1]+=res.s[i+j]/10; res.s[i+j]%=10; } } res.len=a.len+b.len; while(res.s[res.len-1]==0&&res.len>1) res.len--; if(res.s[res.len]) res.len++; return res; } bign operator*(const bign& a,int& b) { bign c=b; return a*c; } //只支持大数减小数 bign operator-(const bign& a,const bign& b) { bign res; int len=a.len; for(int i=0; i<len; i++) { res.s[i]+=a.s[i]-b.s[i]; if(res.s[i]<0) { res.s[i]+=10; res.s[i+1]--; } } while(res.s[len-1]==0&&len>1) len--; res.len=len; return res; } bign operator-(const bign& a,int& b) { bign c=b; return a-c; } bign operator/(const bign& a,const bign& b) { int i,len=a.len; bign res,f; for(i=len-1; i>=0; i--) { f=f*10; f.s[0]=a.s[i]; while(f>=b) { f=f-b; res.s[i]++; } } while(res.s[len-1]==0&&len>1) len--; res.len=len; return res; } bign operator/(const bign& a,int& b) { bign c=b; return a/c; } bign operator%(const bign& a,const bign& b) { int len=a.len; bign f; for(int i=len-1; i>=0; i--) { f=f*10; f.s[0]=a.s[i]; while(f>=b) f=f-b; } return f; } bign operator%(const bign& a,int& b) { bign c=b; return a%c; } bign& operator+=(bign& a,const bign& b) { a=a+b; return a; } bign& operator-=(bign& a,const bign& b) { a=a-b; return a; } bign& operator*=(bign& a,const bign& b) { a=a*b; return a; } bign& operator/=(bign& a,const bign& b) { a=a/b; return a; } bign& operator++(bign& a) { a=a+1; return a; } bign& operator++(bign& a,int) { bign t=a; a=a+1; return t; } bign& operator--(bign& a) { a=a-1; return a; } bign& operator--(bign& a,int) { bign t=a; a=a-1; return t; } istream& operator>>(istream &in,bign& x) { string s; in>>s; x=s.c_str(); return in; } ostream& operator<<(ostream &out,const bign& x) { out<<x.str(); return out; } int main() { bign; return 0; }