Leetcode:mini Parser

Given a nested list of integers represented as a string, implement a parser to deserialize it. Each element was either an integer, or a list--whose elements may also is integers or other lists. Note:you may assume , the string is well-Formed:string is non-empty. String does not contain white spaces. String contains only digits0-9, [,- ,, ]. Example1: Given s= "324", you shouldreturnA Nestedinteger object which contains a single integer 324. Example2: Given s= "[123,[456,[789]]", Return a Nestedinteger object containing a nested list with2elements:1. An integer containing value 123.2. A nested list containing the elements:i. An integer containing value456. Ii. A nested list with one element:a. An integer containing value789.

This is usually used with a stack, stack top is the current Nestedinteger, you can add new elements to it.

Note that the 47 line judgment is critical, incidentally handling "[]," after the parentheses are comma-case

1 /**2 *//This is the interface, allows for creating nested lists.3 *//should not implement it, or speculate on its implementation4 * Public interface Nestedinteger {5 *//Constructor Initializes an empty nested list.6 * public Nestedinteger ();7  *8 *//Constructor Initializes a single integer.9 * Public Nestedinteger (int value);Ten  * One  *     // @returntrue if this nestedinteger holds a single integer, rather than a nested list. A * Public boolean isinteger (); -  * -  *     // @returnThe single integer Nestedinteger holds, if it holds a single integer the *//Return NULL if this nestedinteger holds a nested list - * Public Integer Getinteger (); -  * - *//Set This Nestedinteger-to-hold a single integer. + * public void Setinteger (int value); -  * + *//Set This Nestedinteger-to-hold a nested list and adds a nested an integer to it. A * public void Add (Nestedinteger ni); at  * -  *     // @returnthe nested list that this nestedinteger holds, if it holds a nested list - *//Return NULL if this nestedinteger holds a single integer - * Public list<nestedinteger> getList (); -  * } -  */ in  Public classSolution { -      PublicNestedinteger Deserialize (String s) { to         if(!s.startswith ("[")) { +             return NewNestedinteger (Integer.parseint (s)); -         } theNestedinteger res =NewNestedinteger (); *Stack<nestedinteger> st =NewStack<nestedinteger>(); $ St.push (res);Panax Notoginseng         intStart = 1; -          for(intI=1; I<s.length (); i++) { the             Charc =S.charat (i); +             if(c = = ' [') { ANestedinteger ni =NewNestedinteger (); the St.peek (). Add (NI); + St.push (NI); -Start = I+1; $             } $             Else if(c== ', ' | | c== ') ') { -                 if(I >start) { -                     intval =Integer.parseint (s.substring (Start, i)); theSt.peek (). Add (NewNestedinteger (Val)); -                 }WuyiStart = I+1; the                 if(c = = '] ') St.pop (); -             } Wu         } -         returnRes; About     } $}

Leetcode:mini Parser