LeetCode-173 Largest Number

Title Description

Given a list of non negative integers, arrange them such that they form the largest number.

 

Subject to the effect

Given a non-zero integer array, the array of numbers in a certain order in accordance with a maximum number of composition.

 

Examples

E1

Input: [10,2]
Output: "210"

E2

Input: [3,30,34,5,9]
Output: "9534330"

 

Problem-solving ideas

A simple method, according to certain rules to sort the array, then the array while traversing obtain results.

The rule is: return (a + b), and (b + a) of the larger value.

(PS: a, b are string type)

 

Complexity Analysis

Time complexity: O (nlog (n))

Space complexity: O (n)

 

Code

// size comparison rule 
BOOL CMP ( String A, String B) {
     return (A + B)> (B + A); 
} 

class Solution {
 public :
     String largestNumber (Vector < int > & the nums) { 
        Vector < String > Sn ;
         // the int string into storage 
        for ( int I: the nums) 
            sn.push_back (the to_string (I)); 
        // the string array sorting 
        Sort (sn.begin (), sn.end (), CMP); 
        
        string = ANS "" ;
        for ( int I = 0 ; I <sn.size (); I ++ ) 
            ANS + = Sn [I];
         // The results head '0' to delete 
        the while ! (ans.size () = . 1 && ANS [ 0 ] == ' 0 ' ) 
            ans.erase ( 0 , . 1 ); 
        
        return ANS; 
    } 
};