71. Simplify Path
in Coding Interview on Medium, String, Stack
Unix 스타일 파일 시스템의 파일 또는 디렉터리에 대한 절대 경로(슬래시 ‘/’로 시작)인 문자열 경로가 주어지면 이를 단순화된 표준 경로로 변환
The canonical path should have the following format:
- The path starts with a single slash ‘/’.
- Any two directories are separated by a single slash ‘/’.
- The path does not end with a trailing ‘/’.
- The path only contains the directories on the path from the root directory to the target file or directory (i.e., no period ‘.’ or double period ‘..’)
class Solution {
public String simplifyPath(String path) {
// Initialize a stack
Stack<String> stack = new Stack<String>();
String[] components = path.split("/");
// Split the input string on "/" as the delimiter
// and process each portion one by one
for (String directory : components) {
// A no-op for a "." or an empty string
if (directory.equals(".") || directory.isEmpty()) {
continue;
} else if (directory.equals("..")) {
// If the current component is a "..", then
// we pop an entry from the stack if it's non-empty
if (!stack.isEmpty()) {
stack.pop();
}
} else {
// Finally, a legitimate directory name, so we add it to our stack
stack.add(directory);
}
}
// Stich together all the directory names together
StringBuilder result = new StringBuilder();
for (String dir : stack) {
result.append("/");
result.append(dir);
}
return result.length() > 0 ? result.toString() : "/" ;
}
}
