大数加法类

写了一个大数加法类。内部计算是10000进制的,能省些空间,但是输出的时候要注意补0

 

这个版本的代码只支持正数相加。

 

#include <iostream>using namespace std;struct _cBigNum{const static int def_size = 20;const static int def_jw = 10000;//10000进一 int cvNum[def_size];//0-n从低位到高位 int cvSize;_cBigNum(){clean();}void clean(){cvSize = 0;for( int i = 0;i < def_size;++i )cvNum[i] = 0;}_cBigNum& operator=( const _cBigNum& obj ){clean();cvSize = obj.cvSize;for( int i = 0;i < cvSize;++i )cvNum[i] = obj.cvNum[i];return *this;}_cBigNum& operator=( unsigned long num ){clean();while( num ){cvNum[ cvSize++ ] = num % def_jw;num /= def_jw;}return *this;}_cBigNum operator+( const _cBigNum& obj ){_cBigNum temp;temp.cvSize = cvSize > obj.cvSize ? cvSize : obj.cvSize;int jw = 0;//进位 for( int i = 0;i < temp.cvSize;++i ){temp.cvNum[i] = jw + cvNum[i] + obj.cvNum[i];jw = temp.cvNum[i] / def_jw;temp.cvNum[i] %= def_jw;}if( jw )temp.cvNum[ temp.cvSize++ ] = jw;return temp;}void out(){if( cvSize-1 >= 0 )cout << cvNum[cvSize-1];for( int i = cvSize-2;i >= 0;--i ){//输出补0 for( int j = 1000;j > 1;j /= 10 ){if( cvNum[i] < j )cout << 0;}cout << cvNum[i];}}};int main(){_cBigNum a,b;a = 0x7fffffff;b = 0;for( int i = 0;i < 100;++i ){b = a + b;b.out();cout << endl;a = a + b;a.out();cout << endl;}system("pause");return 0;}