题解：P1158 [NOIP2010 普及组] 导弹拦截

#include <bits/stdc++.h>
using namespace std;
struct s {
	int w1, v1;
	bool operator < (const s &a){//重载
		return w1< a.w1;	
	}
};
int main() {
	int x1, y1, x2, y2;
	cin >> x1 >> y1 >> x2 >> y2;//输入坐标
	int n;
	cin >> n;
	s a[100001];
	int f[100011];
	int cnt = 1<<30;//设置极大值
	for(int i=1;i<=n;i++){
		int x,y;
		cin >> x >> y;
		a[i].w1=(x-x1)*(x-x1)+(y-y1)*(y-y1);//计算距离
		a[i].v1=(x-x2)*(x-x2)+(y-y2)*(y-y2);
	}
	sort(a+1,a+n+1);
	f[n+1]=0;
	for(int i=n;i>=1;i--){
		f[i]=max(f[i+1],a[i].v1);
	}
	for(int i=0;i<=n;i++){
		cnt=min(cnt,a[i].w1+f[i+1]);
	}
	cout << cnt;
	return 0;
}