專題測試三 貪心與動態規劃 G - Children's Game
阿新 • • 發佈：2022-02-17
- 題目
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
4
123 124 56 90
5
123 124 56 90 9
5
9 9 9 9 9
0
Sample Output
9056124123
99056124123
99999 - 思路
對於每兩個數，只有ab和ba兩種排序方式，例如90和9只能排成909或者990，對每個這樣的組合進行比較排出順序，最後出來的排列就是最大的 - 程式碼
#include<cstdio> #include<iostream> #include<string> #include<cstring> #include<algorithm> using namespace std; bool cmp(string &s, string &t) { string st = s + t; string ts = t + s; return st > ts; } int main() { int n; while (cin >> n && n) { string s[55]; int i; for (i = 0; i < n; i++) { cin >> s[i]; } sort(s, s+n, cmp); for (i = 0; i < n; i++) { cout << s[i]; } cout << endl; } return 0; }