424 - Integer Inquiry

简单的高精度加法，LRJ白书的模板。只是脑残了下，忘记回车了

 

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;
const int maxn=1000;
struct bign
{
  int len,s[maxn],flag;//flag 为表示正负备用 
  bign() {memset(s,0,sizeof(s));len=1;}
  bign operator = (const char* num)
  {
      len=strlen(num);
      for(int i=0;i<len;i++) s[i]=num[len-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;
  }
  bign operator + (const bign& b) const
  {
      bign c;
      c.len=0;
      int max=0;
      if(len>b.len) max=len;
      else max=b.len;
      for(int i=0,g=0;g || i<max;i++)
      {
        int x=g;
        if(i<len) x+=s[i];
        if(i<b.len) x+= b.s[i];
        c.s[c.len++]=x%10;
        g=x/10;
      }
      return c;
  }
  
};
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 sum=0;
  char input[500];
  
  while(scanf("%s",&input)&&strcmp(input,"0"))
  {
      bign plus;
      plus=input;
      sum=sum+plus;
  }
  cout<<sum<<endl;//要加回车，唯一的坑 （这哪里是坑？明明是你自己的问题嘛！）
  return 0;
}