#include <iostream>
#include<vector>
#include<string>
using namespace std;
/*Ham doi cho*/
void Swap(int &a, int &b)
{
int temp = a;
a = b;
b = temp;
return;
}
/*Ham kiem tra 2 chuoi ki tu co bao nhieu lan lap*/
int KtraSolanlap(string str1, string str2)
{
int dem = 0;
int j = 0;
for (int i=0; i<str1.length(); i++)
{
while(str2[j]!=str1[i] && j<str2.length())
{
j++;
}
if (j<str2.length()) dem++;
j = 0;
}
return dem;
// Ham nay chua hoan hao lam..... Can chinh sua de nhanh hon nua
// Nhung voi so lieu it, moi sau < 26 ki tu => tam chap nhan.
}
/*Ham kiem tra xem co bao nhieu lan lap trong bo test*/
int KtraTEST(vector<string> str, int n)
{
int dem = 0;
for (int i=0; i<n-1; i++)
{
// Kiem tra chuoi hien tai voi chuoi ke tiep
int temp = KtraSolanlap(str[i],str[i+1]);
dem = dem + temp;
}
return dem;
}
/*Xu li tung hoan vi*/
int XuliHoanVi(int x[], int n, vector<string> str)
{
int arr[n];
for (int i=0; i<n; i++)
arr[i] = x[i+1]-1; // Gan tra lai gia tri arr[0] = 0, arr[1] = 1, arr[2] = 2,...
vector<string> temp;
for (int i=0; i<n; i++)
temp.push_back(str[arr[i]]);
int dem = 0;
dem = KtraTEST(temp,n);
return dem;
}
/*ham in cac hoan vi*/
void InHoanVi(int n, vector<string> str)
{
int x[n+1];
int i;
int k;
int dem = 0, min = KtraTEST(str,n);
for (int j=1; j<=n; j++)
x[j] = j; // Khoi tao x[1] = 1, x[2] = 2, ...
do
{
dem = XuliHoanVi(x,n,str);
if (dem < min) min = dem;
i = n-1;
while(i>0 && x[i] > x[i+1]) i--;
if (i>0) // Chua gap phai phan tu cuoi day
{
k = n; // x[k] la phan tu cuoi day
while(x[k] < x[i]) k--; // Lui dan k de tim phan tu x[k] dau tien lon hon x[i]
Swap(x[k],x[i]); // Doi cho x[k] cho x[i]
int a = i+1, b = n; // Lat nguoc doan cuoi giam dan, a : dau doan, b : cuoi doan
while(a<b)
{
Swap(x[a],x[b]);
a++;
b--;
}
}
} while (i>0);
cout << min << endl;
}
int main()
{
vector<string> str;
int n;
// Nhap du lieu
cin >> n;
for (int i=0; i<n; i++)
{
string temp;
cin >> temp;
str.push_back(temp);
}
InHoanVi(n,str);
//cout << KtraTEST(str,n);
return 0;
}
I2luY2x1ZGUgPGlvc3RyZWFtPgojaW5jbHVkZTx2ZWN0b3I+CiNpbmNsdWRlPHN0cmluZz4KCnVzaW5nIG5hbWVzcGFjZSBzdGQ7CgovKkhhbSBkb2kgY2hvKi8Kdm9pZCBTd2FwKGludCAmYSwgaW50ICZiKQp7CiAgICBpbnQgdGVtcCA9IGE7CiAgICBhID0gYjsKICAgIGIgPSB0ZW1wOwogICAgcmV0dXJuOwp9CgovKkhhbSBraWVtIHRyYSAyIGNodW9pIGtpIHR1IGNvIGJhbyBuaGlldSBsYW4gbGFwKi8KaW50IEt0cmFTb2xhbmxhcChzdHJpbmcgc3RyMSwgc3RyaW5nIHN0cjIpCnsKICAgIGludCBkZW0gPSAwOwogICAgaW50IGogPSAwOwogICAgZm9yIChpbnQgaT0wOyBpPHN0cjEubGVuZ3RoKCk7IGkrKykKICAgIHsKICAgICAgICB3aGlsZShzdHIyW2pdIT1zdHIxW2ldICYmIGo8c3RyMi5sZW5ndGgoKSkKICAgICAgICB7CiAgICAgICAgICAgIGorKzsKICAgICAgICB9CiAgICAgICAgaWYgKGo8c3RyMi5sZW5ndGgoKSkgZGVtKys7CiAgICAgICAgaiA9IDA7CiAgICB9CiAgICByZXR1cm4gZGVtOwogICAgLy8gSGFtIG5heSBjaHVhIGhvYW4gaGFvIGxhbS4uLi4uIENhbiBjaGluaCBzdWEgZGUgbmhhbmggaG9uIG51YQogICAgLy8gTmh1bmcgdm9pIHNvIGxpZXUgaXQsIG1vaSBzYXUgPCAyNiBraSB0dSA9PiB0YW0gY2hhcCBuaGFuLgp9CgovKkhhbSBraWVtIHRyYSB4ZW0gY28gYmFvIG5oaWV1IGxhbiBsYXAgdHJvbmcgYm8gdGVzdCovCmludCBLdHJhVEVTVCh2ZWN0b3I8c3RyaW5nPiBzdHIsIGludCBuKQp7CiAgICBpbnQgZGVtID0gMDsKICAgIGZvciAoaW50IGk9MDsgaTxuLTE7IGkrKykKICAgIHsKICAgICAgICAvLyBLaWVtIHRyYSBjaHVvaSBoaWVuIHRhaSB2b2kgY2h1b2kga2UgdGllcAogICAgICAgIGludCB0ZW1wID0gS3RyYVNvbGFubGFwKHN0cltpXSxzdHJbaSsxXSk7CiAgICAgICAgZGVtID0gZGVtICsgdGVtcDsKICAgIH0KICAgIHJldHVybiBkZW07Cn0KCi8qWHUgbGkgdHVuZyBob2FuIHZpKi8KaW50IFh1bGlIb2FuVmkoaW50IHhbXSwgaW50IG4sIHZlY3RvcjxzdHJpbmc+IHN0cikKewogICAgaW50IGFycltuXTsKICAgIGZvciAoaW50IGk9MDsgaTxuOyBpKyspCiAgICAgICAgYXJyW2ldID0geFtpKzFdLTE7IC8vIEdhbiB0cmEgbGFpIGdpYSB0cmkgYXJyWzBdID0gMCwgYXJyWzFdID0gMSwgYXJyWzJdID0gMiwuLi4KCiAgICB2ZWN0b3I8c3RyaW5nPiB0ZW1wOwogICAgZm9yIChpbnQgaT0wOyBpPG47IGkrKykKICAgICAgICB0ZW1wLnB1c2hfYmFjayhzdHJbYXJyW2ldXSk7CgogICAgaW50IGRlbSA9IDA7CiAgICBkZW0gPSBLdHJhVEVTVCh0ZW1wLG4pOwoKICAgIHJldHVybiBkZW07Cn0KCi8qaGFtIGluIGNhYyBob2FuIHZpKi8Kdm9pZCBJbkhvYW5WaShpbnQgbiwgdmVjdG9yPHN0cmluZz4gc3RyKQp7CiAgICBpbnQgeFtuKzFdOwogICAgaW50IGk7CiAgICBpbnQgazsKICAgIGludCBkZW0gPSAwLCBtaW4gPSBLdHJhVEVTVChzdHIsbik7CiAgICBmb3IgKGludCBqPTE7IGo8PW47IGorKykKICAgICAgICB4W2pdID0gajsgLy8gS2hvaSB0YW8geFsxXSA9IDEsIHhbMl0gPSAyLCAuLi4KICAgIGRvCiAgICB7CiAgICAgICAgZGVtID0gWHVsaUhvYW5WaSh4LG4sc3RyKTsKICAgICAgICBpZiAoZGVtIDwgbWluKSBtaW4gPSBkZW07CgogICAgICAgIGkgPSBuLTE7CiAgICAgICAgd2hpbGUoaT4wICYmIHhbaV0gPiB4W2krMV0pIGktLTsKICAgICAgICBpZiAoaT4wKSAvLyBDaHVhIGdhcCBwaGFpIHBoYW4gdHUgY3VvaSBkYXkKICAgICAgICB7CiAgICAgICAgICAgIGsgPSBuOyAvLyB4W2tdIGxhIHBoYW4gdHUgY3VvaSBkYXkKICAgICAgICAgICAgd2hpbGUoeFtrXSA8IHhbaV0pIGstLTsgLy8gTHVpIGRhbiBrIGRlIHRpbSBwaGFuIHR1IHhba10gZGF1IHRpZW4gbG9uIGhvbiB4W2ldCiAgICAgICAgICAgIFN3YXAoeFtrXSx4W2ldKTsgLy8gRG9pIGNobyB4W2tdIGNobyB4W2ldCgogICAgICAgICAgICBpbnQgYSA9IGkrMSwgYiA9IG47IC8vIExhdCBuZ3VvYyBkb2FuIGN1b2kgZ2lhbSBkYW4sIGEgOiBkYXUgZG9hbiwgYiA6IGN1b2kgZG9hbgogICAgICAgICAgICB3aGlsZShhPGIpCiAgICAgICAgICAgIHsKICAgICAgICAgICAgICAgIFN3YXAoeFthXSx4W2JdKTsKICAgICAgICAgICAgICAgIGErKzsKICAgICAgICAgICAgICAgIGItLTsKICAgICAgICAgICAgfQogICAgICAgIH0KICAgIH0gd2hpbGUgKGk+MCk7CiAgICBjb3V0IDw8IG1pbiA8PCBlbmRsOwp9CmludCBtYWluKCkKewoKICAgIHZlY3RvcjxzdHJpbmc+IHN0cjsKICAgIGludCBuOwoKICAgIC8vIE5oYXAgZHUgbGlldQoKICAgIGNpbiA+PiBuOwogICAgZm9yIChpbnQgaT0wOyBpPG47IGkrKykKICAgIHsKICAgICAgICBzdHJpbmcgdGVtcDsKICAgICAgICBjaW4gPj4gdGVtcDsKICAgICAgICBzdHIucHVzaF9iYWNrKHRlbXApOwogICAgfQoKCgogICAgSW5Ib2FuVmkobixzdHIpOwogICAgLy9jb3V0IDw8IEt0cmFURVNUKHN0cixuKTsKICAgIHJldHVybiAwOwp9