第一行9个整数,R,x1,y1,x2,y2,x3,y3,x0,y0.R代表炮台攻击的最大距离,(x1,y1),(x2,y2), (x3,y3)代表三个炮台的坐标.(x0,y0)代表敌人的坐标.
输出一行,这一行代表敌人承受的最大伤害,(如果每个炮台都不能攻击到敌人,输出0×)
1 1 1 2 2 3 3 1 2
2x
解题
计算距离，比较大小
import java.util.Scanner; public class Main{ public static void main(String[] args){ Scanner in = new Scanner(System.in); while(in.hasNext()){ int r = in.nextInt(); int x1 = in.nextInt(); int y1 = in.nextInt(); int x2 = in.nextInt(); int y2 = in.nextInt(); int x3 = in.nextInt(); int y3 = in.nextInt(); int x0 = in.nextInt(); int y0 = in.nextInt(); long R = r * r; int res = 0; long dis1 = getdistance(x1,y1,x0,y0); long dis2 = getdistance(x2,y2,x0,y0); long dis3 = getdistance(x3,y3,x0,y0); if(dis1<=R) res++; if(dis2<=R) res++; if(dis3<=R) res++; System.out.println(res+"x"); } } public static long getdistance(int x1,int y1,int x0,int y0){ long dis = (x1-x0)*(x1-x0) + (y1-y0)*(y1-y0); return dis; } }
原文：http://www.cnblogs.com/theskulls/p/5280268.html