UVA 10905 Children's Game(贪心 + 水题)

4thIIUCInter-University Programming Contest, 2005
A	Children’s Game
	Input: standard input Output: standard output
	Problemsetter: Md. Kamruzzaman

There are lots of number games for children. These games are pretty easy to play but not so easy to make. We will discuss about an interesting game here. Each player will be given N positive integer. (S)He can make a big integer by appending those integers after one another. Such as if there are 4 integers as 123, 124, 56, 90 then the following integers can be made – 1231245690, 1241235690, 5612312490, 9012312456, 9056124123 etc. In fact 24 such integers can be made. But one thing is sure that 9056124123 is the largest possible integer which can be made.

You may think that it’s very easy to find out the answer but will it be easy for a child who has just got the idea of number?

Input

Each input starts with a positive integer N (≤ 50). In next lines there are N positive integers. Input is terminated by N = 0, which should not be processed.

Output

For each input set, you have to print the largest possible integer which can be made by appending all the N integers.

Sample Input	Output for Sample Input
4 123 124 56 90 5 123 124 56 90 9 5 9 9 9 9 9 0	9056124123 99056124123 99999

题意：给定几个数。要求出这几个数能串出的最大数。

思路：明显的贪心。每两个数字可以有两种组合。所以选择组合出来大的。进行排序。最后按顺序输出就可以了。

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int n, i;
string sb[50];
int cmp(string a, string b) {
	return a + b > b + a;
}
int main() {
	while (cin >> n && n) {
		for (i = 0; i < n; i ++)
			cin >> sb[i];
		sort(sb, sb + n, cmp);
		for (i = 0; i < n; i ++)
			cout << sb[i];
		cout << endl;
	}
	return 0;
}