题解

#include<iostream>
#include<algorithm>
#include<bits/stdc++.h>
using namespace std;
int n,r,a[25],cc;
string A;
void C(int nn,int nm) 
{
	if (nm==r)
	{
		string tmp;
		for (int i=1;i<=r;i++)
			if (a[i]!=1) tmp.push_back(a[i]+'a'-2); 
		if (tmp==A){printf("%d",cc+1); exit(0);} 
		++cc; return ; 
	}
	for (int i=nn+1;i<=n-(r-nm-1);i++) a[nm+1]=i,C(i,nm+1),a[nm+1]=0;
}
int main()
{
	cin>>A; n=27;
	for (r=2;r<=6;r+=2) memset(a,0,sizeof a),C(0,0);
	puts("0");
	return 0;
}