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#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define maxn 111
using namespace std;
int test,n,ans,num,hsh[maxn];
char a[maxn],d[maxn]
;
char c1,c2,c;
void dfs(int x)
{
    if (x>num)
    {
        ans++;
        return;
    }
    for (int i=1;i<=num;i++)
    {
        if (hsh[i]==0)
        {
            hsh[i]=1;
            d[x]=i;
            if (x==1 || (a[d[x-1]]!=a[i])) dfs(x+1);
            hsh[i]=0;
        }
    }
}
int main()
{
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