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please help,why WA?
#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
while(1)
{
long long a,b;
cin>>a>>b;
if(a==0 && b==0)break;
if(a<b)swap(a,b);
int carry=0,flag=0,temp;
while(a)
{
if(flag)
temp=(a%10)+(b%10)+1;
else temp=(a%10)+(b%10);
if(temp>=10)
{

if(a ...