链接: https://www.coursera.org/learn/java-programming/lecture/cI1Vw/seven-steps-in-action-translating-to-code

计算四边形周长的算法

Java

import edu.duke.FileResource;
import edu.duke.Shape;
import edu.duke.Point;
import java.awt.*;
import java.io.FileInputStream;

public class PerimeterRunner {
    public double getPerimeter(Shape s){

        double totalPerim = 0;

        Point prePt = s.getLastPoint();

        for(Point currPt : s.getPoints()){

            double currDist = prePt.distance(currPt);

            totalPerim += currDist;

            prePt = currPt;
        }

        return totalPerim;

    }

    public void testPerimeter(){
        FileResource fr = new FileResource();
        Shape s = new Shape(fr);
        double length = getPerimeter(s);
        System.out.println("perimeter = " + length);

    }

    public static void main(String[] args) {
        PerimeterRunner perimeterRunner = new PerimeterRunner();
        perimeterRunner.testPerimeter();
    }
}