Given an absolute path for a file (Unix-style), simplify it.
For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"
Corner Cases:
Did you consider the case where path = "/../"?
In this case, you should return "/".
Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
In this case, you should ignore redundant slashes and return "/home/foo".
代码语言：javascript复制 public String simplifyPath(String path) {
if (path == null) {
return null;
}
String[] names = path.split("/");
int eat = 0;
LinkedList<String> stack = new LinkedList<String>();
for (int i = names.length - 1; i >= 0; i--) {
String token = names[i];
// token是".."， 表示上级路径，前一个路径不打印
// token是"."， 表示当前路径，自身不打印
// token是"", 表示为两个"/"相连，不做操作
// eat>0，表示左边不打印
// 否则，将token入栈
if (token.equals("..")) {
eat ;
} else if (token.equals(".")) {
// do nothing
} else if (token.equals("")) {
// do nothing
} else {
if (eat > 0) {
eat--;
} else {
stack.push(token);
}
}
}
StringBuilder s = new StringBuilder();
s.append("/");
// 最后一个不加"/"，所以while判断条件是>1
while (stack.size() > 1) {
s.append(stack.pop());
s.append("/");
}
// 最后一个不加"/"
if (!stack.isEmpty()) {
s.append(stack.pop());
}
return s.toString();
}
