C. The Smallest String Concatenation
time limit per test
memory limit per test
input
output
n strings a1, a2, ..., an. You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest.
Given the list of strings, output the lexicographically smallest concatenation.
Input
n — the number of strings (1 ≤ n ≤ 5·104).
n lines contains one string ai (1 ≤ |ai| ≤ 50) consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104.
Output
a
Examples
input
4 abba abacaba bcd er
output
abacabaabbabcder
input
5 x xx xxa xxaa xxaaa
output
xxaaaxxaaxxaxxx
input
3 c cb cba
output
cbacbc
大体题意：
输入n个字符串，把这n个字符串合成一个字符串（就是字符串的拼接），使得这个字符串字典序最小！
思路：
输入字符串后，直接sort就好了！
cmp直接return a + b < b + a，始终按两个字符串相加字典序最小排序！
#include<bits/stdc++.h>
using namespace std;
const int maxn = 50000 + 10;
string s[maxn];
bool cmp(const string &a,const string &b){
return a + b < b + a;
}
int main()
{
int n;
while(scanf("%d",&n) == 1){
for (int i = 0; i < n; ++i)cin >> s[i];
sort(s,s+n,cmp);
for (int i = 0; i < n; ++i)cout << s[i];
printf("\n");
}
return 0;
}
