内存练习 - 综合练习Q37 E07

从 Main 的 run 方法 开始绘制内存

在每个检查点，检查你画的内存是否跟答案一致

练习 1

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public class Point {    public int x;    public int y;     public Point() {    }     public Point(int x, int y) {        this.x = x;        this.y = y;    }}

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public class Main {    public void run() {        Point from = new Point(0, 0);        Point to = new Point(3, 4);        Point[] vector = {from, to};        vector[1].x = 10;        // 检查点    }}

检查点 答案

练习 2

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public class Point {    public int x;    public int y;     public Point() {    }     public Point(int x, int y) {        this.x = x;        this.y = y;    }}

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public class Driver {    psvm () {        new Driver().run();    }    public void run() {        int size = 4;        Point[] points = new Point[size];        Point start = new Point(1, 1);        for (int i = 0; i < size; i++) {            points[i] = start;            start.x += 1;        }        // 检查点     }}

检查点 答案

练习 3

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public class Point {    public int x;    public int y;     public Point() {    }     public Point(int x, int y) {        this.x = x;        this.y = y;    }     public Point added(int deltaX, int deltaY) {        Point result = new Point(x, y);        result.x += deltaX;        result.y += deltaY;        return result;    }}

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public class Driver {    psvm () {        new Driver().run();    }    public void run() {        int size = 4;        Point[] points = new Point[size];        Point start = new Point(1, 1);        Point current = start;        for (int i = 0; i < size; i++) {            points[i] = current;            current = current.added(1, 0);        }        // 检查点     }}

检查点 答案

练习 4

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public class Point {    public int x;    public int y;     public Point() {    }     public Point(int x, int y) {        this.x = x;        this.y = y;    }     public Point added(Point delta) {        Point result = new Point(x, y);        result.x += delta.x;        result.y += delta.y;        return result;    }}

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public class Driver {    psvm () {        new Driver().run();    }    public void run() {        int size = 4;        Point[] points = new Point[size];        Point start = new Point(1, 1);        Point current = start;        for (int i = 0; i < size; i++) {            points[i] = current;            current = current.added(new Point(1, 0));        }        // 检查点    }}

检查点 答案

练习 5

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public class Point {    public int x;    public int y;     public Point() {    }     public Point(int x, int y) {        this.x = x;        this.y = y;    }     public Point added(Point delta) {        Point result = new Point(x, y);        result.x += delta.x;        result.y += delta.y;        return result;    }}

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public class Driver {    psvm () {        new Driver().run();    }    public void run() {        int size = 4;         Point[] directions = new Point[size];        directions[0] = new Point(0, -1);        directions[1] = new Point(1, 0);        directions[2] = new Point(0, 1);        directions[3] = new Point(-1, 0);         Point[] points = new Point[size];        Point center = new Point(1, 1);        for (int i = 0; i < size; i++) {            points[i] = center.added(directions[i]);        }        // 检查点    }}

检查点 答案