如果玩家位置具有列表值，则替换二维数组索引
Replacing 2d array index if player position has values of a list
所以现在当玩家进入一个位置 (pos) 时，例如 A5，如果那里没有船，它将用空字符串替换该棋盘数组索引。但是如果那里有一艘船，我希望它用 hitShip 字符串替换它。
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
switch (pos) {
case "A1":
board[1][2] = empty;
break;
case "B1":
board[1][4] = empty;
break;
case "C1":
board[1][6] = empty;
break;
case "D1":
board[1][8] = empty;
break;
case "E1":
board[1][10] = empty;
break;
case "F1":
board[1][12] = empty;
break;
case "G1":
board[1][14] = empty;
break;
case "H1":
board[1][16] = empty;
break;
case "I1":
board[1][18] = empty;
break;
case "J1":
board[1][20] = empty;
break;
所有坐标 (A1-J10) 的开关盒都适用
ship1 的值为“A6”和“A7”，ship2 的值为“F1”和“F2”。
List ship1 = Arrays.asList(ar[0][0], ar[1][0]);
List ship2 = Arrays.asList(ar[2][0], ar[3][0]);
我有这段代码可以根据玩家是否击中船只来打印 hit/miss 消息，但我不确定如何使用它来用 hitShip 变量替换棋盘数组的索引。
// CHECKS IF THE PLAYER TARGETS HIT SHIP1
boolean hit = false;
for (Object string : ship1) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// CHECKS IF THE PLAYER TARGETS HIT SHIP2
for (Object string : ship2) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// PRINTS HIT/MISS MESSAGE DEPENDING ON WETHER THE PLAYER HIT A SHIP
if (hit) {
System.out.println("\nHit!!!");
} else {
System.out.println("\nMiss!!!");
}
这是完整代码
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;
import javax.sound.midi.Track;
public class Battleship {
static ArrayList<String> playerTargets = new ArrayList<String>();
String[] ship1 = new String[] { ar[0][0], ar[1][0] };
String[] ship2 = new String[] { ar[2][0], ar[3][0] };
// and we'll have an array of all these ships just to make things easier
String[][] ships = new String[] { ship1, ship2 };
public static void main(String[] args) throws FileNotFoundException {
String[][] board = {
{ " ", " ", "A", " ", "B", " ", "C", " ", "D", " ", "E", " ", "F", " ", "G", " ", "H", " ", "I", " ",
"J" },
{ "1", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "2", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "3", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "4", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "5", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "6", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "7", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "8", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "9", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "1", "0", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" ", " " } };
System.out.println("Let's Play Battleship!");
printBoard(board);
for (int i = 1; i < 31; i++) {
Scanner scanner = new Scanner(System.in);
System.out.println("Choose your target Ex.(A3): ");
String pos = scanner.next();
while (playerTargets.contains(pos)) {
System.out.println("Position taken! Please enter a valid position: ");
pos = scanner.next();
}
placePiece(board, pos);
String result = ships(board, pos);
// ENDS THE PROGRAM IF USER HAS HIT ALL THE SHIPS
if (result.length() > 0) {
printBoard(board);
System.out.println();
System.out.println(result);
break;
}
System.out.println("You have " + (30 - i) + " missiles left");
printBoard(board);
}
}
public static void printBoard(String[][] board) {
for (String[] row : board) {
for (String c : row) {
System.out.print(c);
}
System.out.println();
}
}
public static String ships(String[][] board, String pos) throws FileNotFoundException {
// READS SHIP POSITIONS FROM SHIP FILE
String filePath = "/Users/Otez/Desktop/ships.txt";
List<String[]> list = new ArrayList<>();
try {
Scanner scanner = new Scanner(new File(filePath));
while (scanner.hasNextLine()) {
String[] arr = scanner.nextLine().split(",");
for (String item : arr) {
list.add(new String[] { item });
}
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
String[][] ar = list.toArray(String[][]::new);
// CHECKS IF THE PLAYER TARGETS HIT SHIP1
boolean hit = false;
for (Object string : ship1) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// CHECKS IF THE PLAYER TARGETS HIT SHIP2
for (Object string : ship2) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// PRINTS HIT/MISS MESSAGE DEPENDING ON WHETHER THE PLAYER HIT A SHIP
if (hit) {
System.out.println("\nHit!!!");
} else {
System.out.println("\nMiss!!!");
}
// CHECKS IF PLAYER TARGETS HIT THE SHIPS ON THE BOARD
if (playerTargets.contains(ship1) && playerTargets.contains(ship2)) {
return "YOU SANK MY ENTIRE FLEET!!!\n";
}
return "";
}
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
board[firstIndex][secondIndex] = empty;
String characterToPlace = empty;
if (isShip(board, pos)) {
characterToPlace = hitShip;
}
board[firstIndex][secondIndex] = characterToPlace;
}
public static boolean isShip(String[][] board, String pos) {
for (String[] ship : ships) {
for (String shipPos : ship) {
if (shipPos.contains(pos)) {
return true;
}
}
}
return false;
}
}
如您所见，编写和维护大量 switch 语句构成了 not-so-elegant 解决方案。我建议您做的第一件事是清除该代码。仅通过查看，我可以看到随着 pos 的第一个字符中的字母在字母表中前进，您在 board 上使用的第二个索引增加了两个。
所以让我们使用 ASCII 的魔力解决所有这些重复代码：
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
board[firstIndex][secondIndex] = empty;
}
现在无论 pos 是什么，都被标记为空。如果我是你，我现在会有一个单独的方法来确定船只是否被击中 - 尝试使你的代码更加模块化是一种很好的做法。
在我看来你并不真的需要使用列表，你可以只为你的船使用数组：
String[] ship1 = new String[] {ar[0][0], ar[1][0]};
String[] ship2 = new String[] {ar[2][0], ar[3][0]};
//and we'll have an array of all these ships just to make things easier
String[][] ships = new String[] {ship1, ship2};
这些变量最好是全局变量，因为我们不需要在每次检查用户是否击中飞船时都创建它们。
现在我们将创建一个函数来确定某个位置是否有船只 - 请记住，模块化代码更易于更改和维护。我写的和你写的非常相似，只是在使用一系列船时它变得更短了。
public static boolean isShip(String[][] board, String pos) {
for (String[] ship : ships) {
for (String shipPos : ship) {
if (shipPos.contains(pos)) {
return true;
}
}
}
return false;
}
现在，我们只需将新的 isShip 方法合并到重写的 placePiece 方法中：
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
String characterToPlace = empty;
if (isShip(board, pos)) {
characterToPlace = hitShip;
}
board[firstIndex][secondIndex] = characterToPlace;
}
我没有测试过代码，但从代码来看，它应该都能正常工作。通过阅读您的代码，我建议您了解更多信息：
- 以模块化方式构建代码
- 正在编写 'clean' 代码
并且我建议在了解泛型之前不要使用 List。
所以现在当玩家进入一个位置 (pos) 时，例如 A5，如果那里没有船，它将用空字符串替换该棋盘数组索引。但是如果那里有一艘船，我希望它用 hitShip 字符串替换它。
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
switch (pos) {
case "A1":
board[1][2] = empty;
break;
case "B1":
board[1][4] = empty;
break;
case "C1":
board[1][6] = empty;
break;
case "D1":
board[1][8] = empty;
break;
case "E1":
board[1][10] = empty;
break;
case "F1":
board[1][12] = empty;
break;
case "G1":
board[1][14] = empty;
break;
case "H1":
board[1][16] = empty;
break;
case "I1":
board[1][18] = empty;
break;
case "J1":
board[1][20] = empty;
break;
所有坐标 (A1-J10) 的开关盒都适用
ship1 的值为“A6”和“A7”，ship2 的值为“F1”和“F2”。
List ship1 = Arrays.asList(ar[0][0], ar[1][0]);
List ship2 = Arrays.asList(ar[2][0], ar[3][0]);
我有这段代码可以根据玩家是否击中船只来打印 hit/miss 消息，但我不确定如何使用它来用 hitShip 变量替换棋盘数组的索引。
// CHECKS IF THE PLAYER TARGETS HIT SHIP1
boolean hit = false;
for (Object string : ship1) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// CHECKS IF THE PLAYER TARGETS HIT SHIP2
for (Object string : ship2) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// PRINTS HIT/MISS MESSAGE DEPENDING ON WETHER THE PLAYER HIT A SHIP
if (hit) {
System.out.println("\nHit!!!");
} else {
System.out.println("\nMiss!!!");
}
这是完整代码
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;
import javax.sound.midi.Track;
public class Battleship {
static ArrayList<String> playerTargets = new ArrayList<String>();
String[] ship1 = new String[] { ar[0][0], ar[1][0] };
String[] ship2 = new String[] { ar[2][0], ar[3][0] };
// and we'll have an array of all these ships just to make things easier
String[][] ships = new String[] { ship1, ship2 };
public static void main(String[] args) throws FileNotFoundException {
String[][] board = {
{ " ", " ", "A", " ", "B", " ", "C", " ", "D", " ", "E", " ", "F", " ", "G", " ", "H", " ", "I", " ",
"J" },
{ "1", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "2", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "3", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "4", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "5", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "6", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "7", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "8", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "9", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" " },
{ "1", "0", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ", " ",
" ", " " } };
System.out.println("Let's Play Battleship!");
printBoard(board);
for (int i = 1; i < 31; i++) {
Scanner scanner = new Scanner(System.in);
System.out.println("Choose your target Ex.(A3): ");
String pos = scanner.next();
while (playerTargets.contains(pos)) {
System.out.println("Position taken! Please enter a valid position: ");
pos = scanner.next();
}
placePiece(board, pos);
String result = ships(board, pos);
// ENDS THE PROGRAM IF USER HAS HIT ALL THE SHIPS
if (result.length() > 0) {
printBoard(board);
System.out.println();
System.out.println(result);
break;
}
System.out.println("You have " + (30 - i) + " missiles left");
printBoard(board);
}
}
public static void printBoard(String[][] board) {
for (String[] row : board) {
for (String c : row) {
System.out.print(c);
}
System.out.println();
}
}
public static String ships(String[][] board, String pos) throws FileNotFoundException {
// READS SHIP POSITIONS FROM SHIP FILE
String filePath = "/Users/Otez/Desktop/ships.txt";
List<String[]> list = new ArrayList<>();
try {
Scanner scanner = new Scanner(new File(filePath));
while (scanner.hasNextLine()) {
String[] arr = scanner.nextLine().split(",");
for (String item : arr) {
list.add(new String[] { item });
}
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
String[][] ar = list.toArray(String[][]::new);
// CHECKS IF THE PLAYER TARGETS HIT SHIP1
boolean hit = false;
for (Object string : ship1) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// CHECKS IF THE PLAYER TARGETS HIT SHIP2
for (Object string : ship2) {
if (pos.contains((CharSequence) string)) {
hit = true;
break;
}
}
// PRINTS HIT/MISS MESSAGE DEPENDING ON WHETHER THE PLAYER HIT A SHIP
if (hit) {
System.out.println("\nHit!!!");
} else {
System.out.println("\nMiss!!!");
}
// CHECKS IF PLAYER TARGETS HIT THE SHIPS ON THE BOARD
if (playerTargets.contains(ship1) && playerTargets.contains(ship2)) {
return "YOU SANK MY ENTIRE FLEET!!!\n";
}
return "";
}
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
board[firstIndex][secondIndex] = empty;
String characterToPlace = empty;
if (isShip(board, pos)) {
characterToPlace = hitShip;
}
board[firstIndex][secondIndex] = characterToPlace;
}
public static boolean isShip(String[][] board, String pos) {
for (String[] ship : ships) {
for (String shipPos : ship) {
if (shipPos.contains(pos)) {
return true;
}
}
}
return false;
}
}
如您所见，编写和维护大量 switch 语句构成了 not-so-elegant 解决方案。我建议您做的第一件事是清除该代码。仅通过查看，我可以看到随着 pos 的第一个字符中的字母在字母表中前进，您在 board 上使用的第二个索引增加了两个。
所以让我们使用 ASCII 的魔力解决所有这些重复代码：
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
board[firstIndex][secondIndex] = empty;
}
现在无论 pos 是什么，都被标记为空。如果我是你，我现在会有一个单独的方法来确定船只是否被击中 - 尝试使你的代码更加模块化是一种很好的做法。
在我看来你并不真的需要使用列表，你可以只为你的船使用数组：
String[] ship1 = new String[] {ar[0][0], ar[1][0]};
String[] ship2 = new String[] {ar[2][0], ar[3][0]};
//and we'll have an array of all these ships just to make things easier
String[][] ships = new String[] {ship1, ship2};
这些变量最好是全局变量，因为我们不需要在每次检查用户是否击中飞船时都创建它们。
现在我们将创建一个函数来确定某个位置是否有船只 - 请记住，模块化代码更易于更改和维护。我写的和你写的非常相似，只是在使用一系列船时它变得更短了。
public static boolean isShip(String[][] board, String pos) {
for (String[] ship : ships) {
for (String shipPos : ship) {
if (shipPos.contains(pos)) {
return true;
}
}
}
return false;
}
现在，我们只需将新的 isShip 方法合并到重写的 placePiece 方法中：
public static void placePiece(String[][] board, String pos) {
String empty = "0";
String hitShip = "X";
playerTargets.add(pos);
int firstIndex = Character.getNumericValue(pos.charAt(1));
int secondIndex = (pos.charAt(0) - 64) * 2;
String characterToPlace = empty;
if (isShip(board, pos)) {
characterToPlace = hitShip;
}
board[firstIndex][secondIndex] = characterToPlace;
}
我没有测试过代码，但从代码来看，它应该都能正常工作。通过阅读您的代码，我建议您了解更多信息：
- 以模块化方式构建代码
- 正在编写 'clean' 代码
并且我建议在了解泛型之前不要使用 List。