#include<bits/stdc++.h>
using namespace std;
double x,y,xx,yy,n,rx,ry,l,k,max1,max2,num;
inline int read()
{
	int x=0,f=1;char ch=getchar();
	while (ch<'0'||ch>'9'){if (ch=='-') f=-1;ch=getchar();}
	while (ch>='0'&&ch<='9'){x=x*10+ch-48;ch=getchar();}
	return x*f;
}
int main(){
	x=read();y=read();xx=read();yy=read();n=read();
	for(int i=0;i<n;i++){
		rx=read(),ry=read();
		l=sqrt((x-rx)*(x-rx)+(y-ry)*(y-ry));
		k=sqrt((xx-rx)*(xx-rx)+(yy-ry)*(yy-ry));
		if(l<k){
			if(l>max1) max1=l;
		}
		else{
			if(k>max2) max2=k;
		}
	}
	num=max1*max1+max2*max2;
	cout<<num;
	return 0;
}