# include <iostream>
using namespace std;
int main (  )
{

int a,b,c;
while(cin>>a>>b)
{
 c=a-b;
 if (c<0)
 cout<<c*-1<<endl;
 else
 cout<<c<<endl;             
               
               
               
               
               
}               

 return 0;
  }

請把： int a,b,c;

改成：long long a,b,c;

這樣應該就可以過了