Maximum P1107 integer and P1107 integer

Maximum P1107 integer and P1107 integer
Description

There are n positive integers (n <= 20) connected into a row to form a maximum of multiple integers.

For example, when n = 3, the maximum integer connected by 3 integers 13,312,343 is 34331213.

For example, when n = 4, the maximum integer of the 4 integers 7, 13, and 4,246 is 7424613.

Input/Output Format Input Format:

Nn count

Output Format:

Multiple Digits connected

Input and Output sample Input example #1:

313 312 34347 13 4 246

Output sample #1:

343312137424613

Stl is good. I always feel where I have done this.
Note that the condition is not a> B. Otherwise
3
9 90 9 this group of data cannot pass !!

 1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<cmath> 5 #include<algorithm> 6 using namespace std; 7 const int MAXN=21; 8 int read(int & n) 9 {10     char c='.';int x=0,flag=0;11     while(c<'0'||c>'9')12     {13         c=getchar();14         if(c=='-')flag=1;15     }16     while(c>='0'&&c<='9')17     {18         x=x*10+(c-48);19         c=getchar();20     }21     if(flag==1)n=-x;22     else n=x;23 }24 string s[21];25 int comp(const string & a,const string & b)26 {27     return a+b>b+a;28 }29 int main()30 {31     int n;32     while(cin>>n)33     {34         for(int i=1;i<=n;i++)35             cin>>s[i];36         sort(s+1,s+n+1,comp);37         for(int i=1;i<=n;i++)38         cout<<s[i];    39     }40     41     return 0;42 }