题解 | #点的距离#

#include <iostream>
#include <cmath>
using namespace std;
class CPoint {
  public:
    int x, y;
    CPoint(int _x, int _y): x(_x), y(_y) {}
    double operator-(CPoint& p) {
        return sqrt((x - p.x) * (x - p.x) + (y - p.y) * (y - p.y));
    }
};
int main() {
    int m;
    cin >> m;
    while (m--) {
        int x1, y1, x2, y2;
        cin >> x1 >> y1 >> x2 >> y2;
        CPoint p1(x1, y1), p2(x2, y2);
        printf("%.2lf\n", p1 - p2);
    }
}
// 64 位输出请用 printf("%lld")