Leetcode-largest number

Largest number

2015.1.23 20:24

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

For example, given [3, 30, 34, 5, 9] , the largest formed number is 9534330 .

Note:the result May is very large, so you need to return a string instead of an integer.

Solution:

Sort the numbers and piece them together, you'll get the answer, either largest or smallest. As for what to sort them, please see the comparator ().

Time complexity is O (n * log (n)), space complexity are the same, or less.

Accepted Code:

1 //#define ZZ2#include <algorithm>3#include <cstdio>4#include <iostream>5#include <string>6#include <vector>7 using namespacestd;8 9 BOOLComparatorConst string&AMP;S1,Const string&S2)Ten { One     stringS12, S21; A  -S12 = S1 +S2; -S21 = s2 +S1; the  -     BOOLres = S12 <S21; - s12.clear (); - s21.clear (); +  -     returnRes; + } A  at classSolution { -  Public: -     stringLargestnumber (vector<int> &num) { -         Chars[ -]; -vector<string>vs; -  in         intn, I; -  ton = (int) num.size (); +          for(i =0; I < n; ++i) { -sprintf (s),"%d", Num[i]); theVs.push_back (string(s)); *         } $ Panax Notoginseng sort (Vs.begin (), Vs.end (), comparator); -         stringres =""; the  +          for(i = n-1; I >=0; --i) { ARes + =Vs[i]; the         } + vs.clear (); -  $i =0; $n = (int) res.length (); -          while(I < n-1&& Res[i] = ='0') { -++i; the         } -res = RES.SUBSTR (i, N-i);Wuyi  the         returnRes; -     } Wu }; -  About #ifdef ZZ $ intMain () - { -vector<int>num; -     intN; A     inti; + solution Sol; the  -      while(Cin >>N) { $ num.resize (n); the          for(i =0; I < n; ++i) { theCIN >>Num[i]; the         } thecout << sol.largestnumber (num) <<Endl; - num.clear (); in     } the  the     return 0; About } the #endif

Leetcode-largest number