题解 | 牛牛的线段

using System;
public class Program {
    public static void Main() {
        string[] str1 = Console.ReadLine().Split();
        string[] str2 = Console.ReadLine().Split();
        int x1 = int.Parse(str1[0]);
        int y1 = int.Parse(str1[1]);
        int x2 = int.Parse(str2[0]);
        int y2 = int.Parse(str2[1]);
        int s = (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2);
        Console.WriteLine(s);
    }
}