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Why I get wrong answer? I can not understand.[code#include<stdio.h>
int main()
{
long long int a,b,c,d,rem,rem2,k,flag;
while(1)
{
k=0;
scanf("%lld%lld",&c,&d);
if(c<=d)
{
a=d;
b=c;
}
if(c>=d)
{
a=c;
b=d;
}
if(a==0&&b==0)
{
break;
}
flag=0;
for(;;)
{
rem=a%10;
rem2=b%10;
if ...