面試題目兩題寫法

第一題：

題目打印：

java寫法：

  public static void showTree(int level, File parentFolderPath) {
        if (parentFolderPath.isDirectory()) {
            File[] childFiles = parentFolderPath.listFiles();
            for (File file : childFiles) {
                showNameByLevel(level);
                System.out.println(file.getName());
                if (file.isDirectory()) {
                    showTree(level + 1, file);
                }
            }
        }
    }
    public static void showNameByLevel(int level) {
        StringBuffer stringBuffer = new StringBuffer();
        if (level > 0) {
            for (int i = 0; i < level; i++) {
                stringBuffer.append("\t");
            }
        }
        if(stringBuffer.length() >0) System.out.print("|" + stringBuffer);
        System.out.println("|");
        if (stringBuffer.length()>0) System.out.print("|" + stringBuffer);
        System.out.print("----");
    }
    @Test
    public void c23() {
        File file = new File("D:\\TOOL\\IDEASpace\\mavedome\\src\\test\\java");
//        printlen(file, 0);
        showTree(0, file);
    }

python寫法：

def fileCntIn(currPath):
    '''''匯總當前目錄下文件數'''
    sum = 0
    for root, dirs, files in os.walk(currPath, topdown=False):
        for flie in files:
            sum += len(flie)
    return sum

    # return sum([len(files) for root, dirs, files in os.walk(currPath,topdown=False)])

def dirsTree(startPath):
    '''''樹形打印出目錄結構'''
    for root, dirs, files in os.walk(startPath):
        # 獲取當前目錄下文件數
        fileCount = fileCntIn(root)
        # 獲取當前目錄相對輸入目錄的層級關系,整數類型
        level = root.replace(startPath, '').count(os.sep)
        # 樹形結構顯示關鍵語句
        # 根據目錄的層級關系，重復顯示'| '間隔符，
        # 第一層 '| '
        # 第二層 '| | '
        # 第三層 '| | | '
        # 依此類推...
        # 在每一層結束時，合并輸出 '|____'
        indent = '| ' * 1 * level + '|____'
        print('%s%s -r:%s' % (indent, os.path.split(root)[1], fileCount))
        for file in files:
            indent = '| ' * 1 * (level + 1) + '|____'
            print('%s%s' % (indent, file))

if __name__ == '__main__':
    dirsTree(os.getcwd())

第二題：

判斷一些哪里有問題，如果有問題，怎么修改。

  FileInputStream fileInputStream = null;
        FileOutputStream fileOutputStream = null;
        try {
            fileInputStream = new FileInputStream("ttt");
            fileOutputStream = new FileOutputStream("bbb");
        }

修改為：

 FileInputStream fileInputStream = null;
        FileOutputStream fileOutputStream = null;
        try {
            fileInputStream = new FileInputStream("ttt");
            fileOutputStream = new FileOutputStream("bbb");
            int len = 0;
            while ((len = fileInputStream.read()) != 0) {
                fileOutputStream.write(len);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (fileInputStream != null) {
                try {
                    fileInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fileOutputStream != null) {
                try {
                    fileOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

寫法：

public static void main(String[] args) {
        FileInputStream fis = null;
        FileOutputStream fos = null;
        try {
            fis = new FileInputStream("aaa.txt");
            fos = new FileOutputStream("bbb.txt");
            int b;
            while ((b = fis.read()) != -1) {
                fos.write(b);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (fis != null) {
                try {
                    fis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}