UVA10098 Generating Fast

 

Generating Fast, Sorted Permutation

Input: Standard Input

Output: Standard Output

 

Generating permutation has  always been an important problem in computer science. In this problem you will  have to generate the permutation of a given string in ascending order.  Remember that your algorithm must be  efficient.

Input

The first line of the  input contains an integer n, which indicates how many strings to follow. The  next n lines contain n strings. Strings will only contain alpha numerals and  never contain any space. The maximum length of the string is  10.

  Output

For each input string  print all the permutations possible in ascending order. Not that the strings  should be treated, as case sensitive strings and no permutation should be  repeated. A blank line should follow each output set.

 

Sample Input

3 ab abc bca

 

 

Sample  Output

ab

ba

abc

acb

bac

bca

cab

cba

abc

acb

bac

bca

cab

cba

 

题意：不重复的输出所有组合

分析：全排列，next_permutation()

代码如下：

#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;
bool cmp(char a,char b)
{
    return a<b;
}
int main()
{
    int n,i,l;char a[11];
    cin>>n;
    for(i=0;i<n;i++)
    {
        cin>>a;
        l=strlen(a);
        sort(a,a+l,cmp);
        cout<<a<<endl;
        while(next_permutation(a,a+l))
        {
            cout<<a<<endl;
        }
        cout<<endl;
    }
    return 0;
}