#include <bits/stdc++.h>
using namespace std;

#ifdef genshin
#include <experimental/iterator>
#endif
const int INF = 0x3F3F3F3F;
const int maxn = 16;
char s[maxn+1];
int dis[maxn + 1][1 << maxn];
signed main() { ios::sync_with_stdio(0); cin.tie(0);
    int n;
    cin >> n;
    vector<pair<int, int>> num(n); // len, mask
    for(int i=0;i<n;++i){
		scanf("%s",s+1);
		int x=0,len=0;
		for(int j=1;j<=strlen(s+1);++j)x|=(s[j]-'0')<<len,++len;
		num[i]={strlen(s+1),x};
	}
    memset(dis, 0x3f, sizeof dis);
    priority_queue<tuple<int, int, int>, vector<tuple<int, int, int>>, greater<tuple<int, int, int>>> pq;
    for (const auto &[len1, mask1] : num)
        for (const auto &[len2, mask2] : num) {
            if (len1 == len2 && mask1 == mask2)
                continue;
            if (len1 < len2)
                continue;
            if ((mask1 & ((1 << len2) - 1)) != mask2)
                continue;
            int nxt_mask = mask1 >> len2;
            int nxt_len = len1 - len2;
            if (dis[nxt_len][nxt_mask] > len1) {
                dis[nxt_len][nxt_mask] = len1;
                pq.push({len1, nxt_len, nxt_mask});
            }
        }
//    while (!pq.empty()) {
//        auto [d, len, mask] = pq.top();
//        pq.pop();
//        if (d > dis[len][mask])continue;
//        for (const auto &[new_len, new_mask] : num) {
//            int nxt_mask, nxt_len;
//            if (new_len <= len) {
//                if ((mask & ((1 << new_len) - 1)) != new_mask)
//                    continue;
//                nxt_mask = mask >> new_len;
//                nxt_len = len - new_len;
//            }
//            else {
//                if ((new_mask & ((1 << len) - 1)) != mask)
//                    continue;
//                nxt_mask = new_mask >> len;
//                nxt_len = new_len - len;
//            }
//            int cost = max(0, new_len - len);
//            if (dis[nxt_len][nxt_mask] > d + cost) {
//                dis[nxt_len][nxt_mask] = d + cost;
//                pq.push({d + cost, nxt_len, nxt_mask});
//            }
//        }
//    }
    while(!pq.empty()){
		auto [d,len,val]=pq.top();pq.pop();
		if(d>dis[len][val])continue;
		for(int i=0;i<num.size();++i){
			int len2=num[i].first,val2=num[i].second,nxt_len,nxt_val,flag=0;
			if(len>=len2&&((val&((1<<len2)-1))==val2))nxt_len=len-len2,nxt_val=val>>len2,flag=1;
			else if(len<len2&&(val2&((1<<len)-1))==val)nxt_len=len2-len,nxt_val=val2>>len,flag=1;
			if(!flag)continue;
			int cost=max(0,len2-len);
			if(d+cost<dis[nxt_len][nxt_val])dis[nxt_len][nxt_val]=d+cost,pq.push({d+cost,nxt_len,nxt_val});
		}
	}
    if (dis[0][0] == INF)
        cout << "0\n";
    else
        cout << dis[0][0] << '\n';
}