剑指Offer31 把数组排成最小的数

 1 /*************************************************************************
 2     > File Name: 31_SortArrayMin.cpp
 3     > Author: Juntaran
 4     > Mail: JuntaranMail@gmail.com
 5     > Created Time: 2016年09月02日 星期五 11时10分42秒
 6  ************************************************************************/
 7 
 8 #include <stdio.h>
 9 #include <string>
10 #include <bits/stdc++.h>
11 
12 using namespace std;
13 
14 string itos(int x)
15 {
16     return (x>9 ? itos(x/10) : "") + char(x%10 + ‘0‘);
17 }
18 
19 bool cmp(const void *a,const void *b)
20 {
21     return (itos(a) + itos(b)) < (itos(b) + itos(a));
22 }
23 
24 bool compare(int a, int b)
25 {
26     return (itos(a) + itos(b)) < (itos(b) + itos(a));
27 }
28 
29 string PrintMinNumber(int* nums, int length)
30 {
31     string s = "";
32     if (nums==NULL || length<=0)
33         return s;
34 //    sort(nums, nums+length, cmp);
35     qsort(nums, length, sizeof(int), cmp);
36     
37     for (int i = 0; i < length; ++i)
38         s += itos(nums[i]);
39     cout << s << endl;
40     return s;
41 }
42 
43 int main()
44 {
45     int nums[] = {3, 32, 321};
46     int length = 3;
47     PrintMinNumber(nums, length);
48     
49     return 0;
50 }