Description
Dr lee cuts a string S into N pieces,s[1],…,s[N].
Now, Dr lee gives you these N sub-strings: s[1],…s[N]. There might be several possibilities that the string S could be. For example, if Dr. lee gives you three sub-strings {“a”,“ab”,”ac”}, the string S could be “aabac”,”aacab”,”abaac”,…
Your task is to output the lexicographically smallest S.
Input
The first line of the input is a positive integer T. T is the number of the test cases followed.
The first line of each test case is a positive integer N (1 <=N<= 8 ) which represents the number of sub-strings. After that, N lines followed. The i-th line is the i-th sub-string s[i]. Assume that the length of each sub-string is positive and less than 100.
Output
The output of each test is the lexicographically smallest S. No redundant spaces are needed.
Sample Input
1 3 a ab ac
Sample Output
aabac
水题，做一个比较就可以了。比较A+B和B+A
1 #include<iostream>
2 #include<string>
3 #include<vector>
4 #include<algorithm>
5 using namespace std;
6 bool cmp (string a, string b) {
7 return a + b > b + a;
8 }
9 int main() {
10 int t;
11 cin >> t;
12 while (t--) {
13 int n;
14 string a;
15 vector<string> q;
16 cin >> n;
17 while (n--) {
18 cin >> a;
19 q.push_back(a);
20 }
21 sort(q.begin(), q.end(), cmp);
22 while (!q.empty()) {
23 cout << q.back();
24 q.pop_back();
25 }
26 cout << endl;
27 }
28 return 0;
29 }