poj 1256 Anagram

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
bool cmp(const char &a, const char &b)
{
if(a<='Z' && a>='A' && b<='Z' && b>='A')
return a<b;
if(a<='z' && a>='a' && b<='z' && b>='a')
return a<b;
if(a<='Z' && a>='A' && b<='z' && b>='a')
return a+'a'-'A'<=b;
if(a<='z' && a>='a' && b<='Z' && b>='A')
return a<b+'a'-'A';
}
int main(){
char a[20];
int i,len,n;
scanf("%d",&n);
while(n--){
scanf("%s",a);
len=strlen(a);
sort(a,a+len,cmp);
do{
printf("%s\n",a);
}while(next_permutation(a,a+len,cmp));
}
return 0;
}