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//大数类

#include<iostream> #include<string> #include<iomanip> #include<algorithm> using namespace std;

#define MAXN 9999

#define DLEN 4

class BigNum{

private:    int a[300];//DLEN digs for a position    int len; public:    BigNum(){len = 1;memset(a,0,sizeof(a));}    BigNum(const int b);    BigNum(const BigNum & T);

   bool     Bigger(const BigNum &) const;

   BigNum & operator=(const BigNum &);    BigNum & Add(const BigNum &);    BigNum & Sub(const BigNum &);    BigNum operator+(const BigNum &) const;    BigNum operator-(const BigNum &) const;    BigNum operator*(const BigNum &) const;    BigNum operator/(const int   &) const;    void Print(); }; BigNum::BigNum(const int b) {    int c,d = b;

   len = 0;

   memset(a,0,sizeof(a));    while(d > MAXN){       c = d - d / (MAXN + 1) * (MAXN + 1);       d = d / (MAXN + 1);       a[len++] = c;    }    a[len++] = d; } BigNum::BigNum(const BigNum & T) : len(T.len) {    int i;    memset(a,0,sizeof(a));    for(i = 0 ; i < len ; i++)       a[i] = T.a[i]; } bool  BigNum::Bigger(const BigNum & T) const {    int ln;    if(len > T.len) return true;    else if(len == T.len){       ln = len - 1;       while(a[ln] == T.a[ln] && ln >= 0) ln--;       if(ln >= 0 && a[ln] > T.a[ln]) return true;       else return false;    }    else return false; } BigNum & BigNum::operator=(const BigNum & n) {    len = n.len;    memset(a,0,sizeof(a));    for(int i = 0 ; i < len ; i++)       a[i] = n.a[i];    return *this; } BigNum & BigNum::Add(const BigNum & T) {    int i,big;

   big = T.len > len ? T.len : len;

   for(i = 0 ; i < big ; i++)    {       a[i] = a[i] + T.a[i];       if(a[i] > MAXN)       {          a[i + 1]++;          a[i] = a[i] - MAXN - 1;       }    }    if(a[big] != 0) len = big + 1;    else len = big;

   return *this;

} BigNum & BigNum::Sub(const BigNum & T) {    int i,j,big;

   big = T.len > len ? T.len : len;

   for(i = 0 ; i < big ; i++){       if(a[i] < T.a[i]){          j = i + 1;          while(a[j] == 0) j++;          a[j--]--;          while(j > i) a[j--] += MAXN;          a[i] = a[i] + MAXN + 1 - T.a[i];       }       else a[i] -= T.a[i];    }    len = big;    while(a[len - 1] == 0 && len > 1) len--;    return *this; } BigNum BigNum::operator+(const BigNum & n) const {    BigNum a = *this;

   a.Add(n);

   return a; } BigNum BigNum::operator-(const BigNum & T) const {    BigNum b = *this;

   b.Sub(T);

   return b; } BigNum BigNum::operator*(const BigNum & T) const {    BigNum ret;    int i,j,up;    int temp,temp1;

   for(i = 0 ; i < len ; i++){

      up = 0;       for(j = 0 ; j < T.len ; j++){          temp = a[i] * T.a[j] + ret.a[i + j] + up;          if(temp > MAXN){             temp1 = temp - temp / (MAXN + 1) * (MAXN + 1);             up = temp / (MAXN + 1);             ret.a[i + j] = temp1;          }          else {             up = 0;             ret.a[i + j] = temp;          }       }       if(up != 0)          ret.a[i + j] = up;    }    ret.len = i + j;    while(ret.a[ret.len - 1] == 0 && ret.len > 1) ret.len--;    return ret; } BigNum BigNum::operator/(const int & b) const {    BigNum ret;    int i,down = 0;

   for(i = len - 1 ; i >= 0 ; i--){

      ret.a[i] = (a[i] + down * (MAXN + 1)) / b;       down = a[i] + down * (MAXN + 1) - ret.a[i] * b;    }    ret.len = len;    while(ret.a[ret.len - 1] == 0) ret.len--;    return ret; } void BigNum::Print() {    int i;

   cout << a[len - 1];

   for(i = len - 2 ; i >= 0 ; i--){       cout.width(DLEN);       cout.fill('0');       cout << a[i];    }    cout << endl; }

 

大数 加法：

#include <stdio.h>

#include <stdlib.h>#include <string.h>#define MAX_BIT 1000void add(char *re,char *op1,char *op2){     int i=0,cf=0,temp,m1,m2;    while(1)    {         if(*op1)m1=*op1-48,++op1;        else m1=0;        if(*op2)m2=*op2-48,++op2;        else m2=0;        temp=m1+m2+cf;        cf=temp/10;        re[i++]=temp%10+48;        if(!*op1&&!*op2)        {             if(cf)re[i++]=cf+48;            re[i]=0;            break;        }    }}void make(char *op1,char *op2){     char re[MAX_BIT];    int i=0;    add(re,strrev(op1),strrev(op2));    strrev(re);    while(*(re+i)=='0')i++;    printf("%s/n",re+i);}int main(){     char op1[MAX_BIT],op2[MAX_BIT];    scanf("%s%s",op1,op2);    make(op1,op2);    system("PAUSE");    return 0;}

 

//-------------------------------------------

//   大整数加法.////   利用字符数组模拟实现大数加法运算////   2006-11-30//-------------------------------------------

#include <iostream.h>

#include <stdlib.h>#include <string.h>

#define   min( x ,y )   ( x>y )?   y : x;

#define   max( x ,y )   ( x>y )?   x : y;#define   len           100

int main()

{      char   s1[ len-1 ] ,s2[ len-1 ] ;     char   s[ len ] ;          cout<<"Input a number:( <10^"<<len<<" )"<<endl;     cin>>s1;     cout<<"Input the other number:( <10^"<<len<<" )"<<endl;     cin>>s2;     int   len1 = strlen( s1 );     int   len2 = strlen( s2 );          int   grad = 0;//进位标志     int   minl = min( len1 , len2 );     int   maxl = max( len1 , len2 );          int   i ,j ;          for( i=0 ; i<minl ; i++ )//第一步：处理公共部分     {            s[ len-1-i ] = ( grad + s1 [ len1-1-i ] + s2[ len2-1-i ] - '0' - '0' )%10;           grad = ( grad + s1[ len1-1-i ] + s2[ len2-1-i ] - '0' - '0' )/10;     }          for( ; i<maxl ; i++ )//第二步：处理截断的部分     {            if( len1>len2 )           {                  s[ len-1-i ] = ( grad + s1[ len1-1-i ] - '0' )%10;                 grad = ( grad + s1[ len1-1-i ] - '0' )/10;           }           else           {                  s[ len-1-i ] = (grad + s2[ len2-1-i ]- '0' )%10;                 grad = ( grad + s2[ len2-1-i ] - '0' )/10;           }                }          while( grad&&i<len )//处理进位的情况     {            s[ len-1-i ] = grad%10;           grad = grad/10;           ++i;     }          if( i>=len-1 )//若结果存不下，提示.     {            cout<<"The store is too short!/n";           exit(1);     }          cout<<"Reslut is:/n";//打印结果     for( j=i ; j>0 ; j-- )           cout<<int( s[ len-j ] );     cout<<endl;          return 1;} 

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