Question

这是我的java代码（我知道的一种可怕的暴力算法，这是要求）。我想我在任何引用之前已经在for循环中初始化了j变量，但是当我运行编译器警报时。

import java.util.Arrays;

public class Brute {

    public static void main(String[] args) {

        String filename = "./collinear/input" + args[0] + ".txt";
        In f = new In(filename);
        int N = f.readInt();
        Point[] points = new Point[N];
        int x, y;

        StdDraw.setScale(-10000, 50000);

        for(int i = 0; i < N; i++) {
            x = f.readInt();
            y = f.readInt();
            points[i] = new Point(x, y);
            points[i].draw();
        }

        Arrays.sort(points);


        int i, j, k, l;

        for(i = 0; i < N; i++)
            for(j = 0; j < N; j++)
                if(points[j] == points[i]) continue;
                for(k = 0; k < N; k++)
                    if((points[k] == points[i]) || (points[k] == points[j])) continue;
                    for(l = 0; l < N; l++) {
                        if((points[l] == points[i]) || (points[l] == points[j])
                            || (points[l] == points[k])) continue;
                        if(points[i].slopeTo(points[j]) == points[i].slopeTo(points[k])
                        && points[i].slopeTo(points[k]) == points[i].slopeTo(points[l])) {
                            StdOut.println(points[i].toString() 
                            + " -> " + points[j].toString() 
                            + " -> " + points[k].toString() 
                            + " -> " + points[l].toString());

                            points[i].drawTo(points[l]);
                        }
                    }       

    }
}

Brute.java:31：错误：变量j可能尚未初始化

if((points[k] == points[i]) || (points[k] == points[j])) continue;

Brute.java:33：错误：变量j可能尚未初始化

if((points[l] == points[i]) || (points[l] == points[j])

Answer 1

在for循环的主体周围放置大括号。

此：

for(j = 0; j < N; j++)
    if(points[j] == points[i]) continue;
    for(k = 0; k < N; k++) .....

是一行的for循环，没有做任何事情，接着是另一行for循环。

你的意思是：

for(j = 0; j < N; j++) {
    if(points[j] == points[i]) continue;
    for(k = 0; k < N; k++) {
        .....
    }
}

变量可能尚未初始化？

1 个答案: