mathint.h

RSA加密算法的实现 2^1024大的素数实现

//The definition of mathInt,range:-2^1024--->2^1024;
#ifndef _CLASS_MATHINT_
#define _CLASS_MATHINT_
#include<cstdlib>
#include<iostream>
#include<fstream>
#include<string>
#include<vector>
#include<time.h>

using namespace std;
const int BASE=256;
const int VSIZE=128;
class mathInt
{
private:
	bool sign;
	vector<int> coeff;
public:
	mathInt(bool isPos=1){sign = isPos;coeff.resize(VSIZE); }
	mathInt(int integer);
	mathInt(bool isPos,vector<int> v){ sign = isPos; coeff = v; }
	~mathInt(){}

    void set_coeff(bool isPos,int size);//set size nonzero coefficients;
	bool get_sign()const{ return sign;}
	int length()const;
	const vector<int> get_coeff()const{ return coeff;}
	mathInt abs()const;
	void display()const;
	void OutToFile(char* name)const;
	void OutToString(char* name,bool flag)const;
	bool is_odd()const;
	bool is_pos()const;
	
	//overload operator
	int  operator [](int i)const;
	mathInt operator - ()const{ return mathInt(!sign,coeff);} 
    bool operator < (mathInt const& a)const;
	bool operator <=(mathInt const& a)const;
	bool operator ==(mathInt const &a)const;
	bool operator ==(int const& a)const;
	mathInt operator >>(int n)const;//keep the original mathInt,return (*this)*BASE^n;
	void operator = (mathInt const & a);
    void operator = (int const & n);
	
	mathInt operator +(mathInt const& a)const;
	mathInt operator +(int const& a)const;
	mathInt operator -(mathInt const& a)const;
	mathInt operator -(int const& a)const;
	mathInt operator *(int n)const;
	mathInt operator *(mathInt const& a)const;
	mathInt operator /(mathInt const& a)const;
	mathInt operator /(int const & a)const;
	mathInt operator %(mathInt const& a)const;

};//class mathInt, the num may be negative
const mathInt ZERO;
#endif