ACdream 1061:郭氏树

把A当作原点就可以了

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
typedef long long LL;
int main()
{
    LL x,y;
    int t;
    scanf("%d",&t);
    unsigned long long z;
    while(t--)
    {
        scanf("%lld%lld",&x,&y);
        if(y>x) z=y-x;
        else z=x-y;
        printf("%llu\n",z);
    }
    return 0;
}