uva 10035 - Primary Arithmetic

题目信息：10035 - Primary Arithmetic

   题目不难，刚开始的时候1 999999这组数据没考虑。

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

int main()
{
    string line,line1,line2;
    int carry,carryNum;
    while(cin>>line1>>line2)
    {
        if(line1 == "0" && line2=="0") break;
        else
        {
            carry=carryNum=0;
             int len1,len2;
             len1=line1.length()-1;
             len2=line2.length()-1;
             while(len1>=0 && len2>=0)
             {
                  if(line1[len1--]+line2[len2--]-'0'-'0'+carry>=10)
                  {
                      carry=1;
                      carryNum++;
                  }
                  else
                      carry=0;
             }
             //判断比较大的那个数加上carry是否进位，就是carry =1 时，下一位是否为9
             while(carry==1)
             {
                 if(len1>=0 && line1[len1--]== '9') carryNum++;
                 else if(len2>=0 && line2[len2--]=='9') carryNum++;
                 else carry=0;
             }
             //输出
             if(carryNum==0) cout<<"No carry operation."<<endl;
            else if(carryNum==1) cout<<carryNum<<" carry operation."<<endl;
            else cout<<carryNum<<" carry operations."<<endl;
        }
    }    
    return 0;
}