#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <cstdlib>
#include <ctime>

using namespace std;

string a,b;

class ReversalChain {
public:
	int minReversal(string, string);
};

int dp[101][101][102][4];
const int INF=99999999;
int solve(int L,int R,int start,int direction){
	int d = direction ? -1 : 1;
	bool ok=true;
	for(int i=L;i<R;i++){
		if(b[i] != a[start + (i-L)*d]){
			ok=false;
			break;
		}
	}
	if(ok)return 0;
	if(dp[L][R][start][direction]>=0)return dp[L][R][start][direction];
	int &ret = dp[L][R][start][direction];
	ret=INF;
	for(int l=L;l<R;l++){
		for(int r=R;r>=l;r--){
			if(l==L&&r==R){

			}else{
				if(direction == 0){
					ret = min(ret,
							solve(l,r,start + (r - L) - 1,1) + 1);
				}else{
					ret = min(ret,
							solve(l,r,start - (r - L) + 1, 0) + 1);
				}
			}
			if(b[r-1] != a[start + (r-1-L)*d]){
				break;
			}
		}
		if(b[l] != a[start + (l-L)*d])break;
	}
	cout<<L<<","<<R<<","<<start<<","<<direction<<":"<<ret<<endl;
	return ret;
}
int ReversalChain::minReversal(string init, string goal) {
	memset(dp,-1,sizeof(dp));
	a=init;
	b=goal;
	int ret=solve(0,init.size(),0,0);
	memset(dp,-1,sizeof(dp));
	reverse(a.begin(),a.end());
	ret=min(ret,solve(0,init.size(),0,0)+1);
	if(ret>=INF)ret=-1;
	return ret;
}