#include<bits/stdc++.h>
using namespace std;
#define INF 0x3f3f3f3f
#define PI acos(-1)
#define io ios::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define mem(a,b) memset((a),(b),sizeof(a))
typedef long long ll;
typedef unsigned long long ull;
#define int long long
#define db long double

const double eps = 1e-6;
int mod = 1000000000000002493;
const int maxn = 550;

int m[maxn][maxn];
int ans[maxn];//解
int con;//0表示唯一解 1表示多解 2表示无解
int n;

int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
int lcm(int a, int b) { return a / gcd(a, b) * b; }

void mul(int a, int p) {//第a行同乘p
    for (int i = 1;i <= n + 1;i++) {
        m[a][i] *= p;
    }
}
void sub(int a, int x, int b, int y) {//第a行的x倍减去b行的y倍
    for (int i = 1;i <= n + 1;i++) {
        m[a][i] = m[a][i] * x - m[b][i] * y;
    }
}
void exch(int a, int b) {//交换a,b两行
    for (int i = 1;i <= n + 1;i++) {
        m[a][i] ^= m[b][i];
        m[b][i] ^= m[a][i];
        m[a][i] ^= m[b][i];
    }
}
void gauss() {//n阶矩阵，标准矩阵
    for (int i = 1;i <= n;i++) {
        if (m[i][i] == 0) {
            for (int j = i + 1;j <= n;j++) {
                if (m[j][i]) { exch(i, j); }
            }
            if (m[i][i] == 0) {
                con = 1;
                continue;
            }
        }
        for (int j = 1;j <= n;j++) {
            if (j != i) {
                int s1 = m[i][i];
                int s2 = m[j][i];
                if (s2 == 0) continue;
                else {
                    int g = gcd(s1, s2);
                    sub(j, s1 / g, i, s2 / g);
                }
            }
        }
    }
    if (con == 0) {
        for (int i = 1;i <= n;i++) {
            ans[i] = m[i][n + 1] / m[i][i];
        }
    }
}

string s[maxn][maxn];
string name[maxn], AN[maxn];
int lll[maxn], l[maxn][maxn];

inline bool check1(int i, int j) {
    if (j == 1) return true;
    if (i != 1) {
        for (int ii = 0; ii < lll[i]; ii++) {
            if (s[i][1][ii] != s[i][j][ii]) return false;
        }
    }
    for (int ii = 0; ii < lll[j]; ii++) {
        if (s[j][1][ii] != s[i][j][ii + lll[i]]) return false;
    }
    return true;
}

inline bool check() {
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            if (i != j) {
                if (l[i][j] != lll[i] + lll[j]) {
                    return false;
                }
            }
        }
    }
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            if (i != j) {
                if (!check1(i, j)) {
                    return false;
                }
            }
        }
    }
    return true;
}

bool run(int len) {
    name[1] = s[1][2].substr(0, len);
    lll[1] = len;
    int flag = 1;
    for (int i = 2; i <= n; i++) {
        lll[i] = s[i][1].length() - lll[1];
        if (lll[i] <= 0) {
            flag = 0;
            break;
        }
    }
    if (flag == 0) return false;
    if (check()) {
        AN[1] = name[1];
        for (int i = 2; i <= n; i++) {
            for (int j = 0; j < lll[i]; j++) {
                AN[i] += s[i][1][j];
            }
        }
        return true;
    }
    else {
        return false;
    }
}

ull h[1000010], base[1000010], h1[1000010], base1[1000010], h2[1000010], base2[1000010], h12[1000010], base12[1000010];
ull query(int l, int r)//获取字符串[l,r]的哈希值
{
    return h[r] - h[l - 1] * base[r - l + 1];
}
ull query1(int l, int r)//获取字符串[l,r]的哈希值
{
    return h1[r] - h1[l - 1] * base1[r - l + 1];
}
ull query2(int l, int r)//获取字符串[l,r]的哈希值
{
    return h2[r] - h2[l - 1] * base2[r - l + 1];
}
ull query12(int l, int r)//获取字符串[l,r]的哈希值
{
    return h12[r] - h12[l - 1] * base12[r - l + 1];
}

void init(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h[i] = h[i - 1] * 233 + s[i];
        base[i] = base[i - 1] * 233;// base[i]=M^i
    }
}

void init1(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base1[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h1[i] = h1[i - 1] * 233 + s[i];
        base1[i] = base1[i - 1] * 233;// base[i]=M^i
    }
}

void init2(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base2[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h2[i] = h2[i - 1] * 131 + s[i];
        base2[i] = base2[i - 1] * 131;// base[i]=M^i
    }
}
void init12(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base12[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h12[i] = h12[i - 1] * 131 + s[i];
        base12[i] = base12[i - 1] * 131;// base[i]=M^i
    }
}
ull h4[1000010], base4[1000010], h14[1000010], base14[1000010], h24[1000010], base24[1000010], h124[1000010], base124[1000010];
ull query4(int l, int r)//获取字符串[l,r]的哈希值
{
    return h4[r] - h4[l - 1] * base4[r - l + 1];
}
ull query14(int l, int r)//获取字符串[l,r]的哈希值
{
    return h14[r] - h14[l - 1] * base14[r - l + 1];
}
ull query24(int l, int r)//获取字符串[l,r]的哈希值
{
    return h24[r] - h24[l - 1] * base24[r - l + 1];
}
ull query124(int l, int r)//获取字符串[l,r]的哈希值
{
    return h124[r] - h124[l - 1] * base124[r - l + 1];
}

void init4(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base4[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h4[i] = h4[i - 1] * 13331 + s[i];
        base4[i] = base4[i - 1] * 13331;// base[i]=M^i
    }
}

void init14(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base14[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h14[i] = h14[i - 1] * 13331 + s[i];
        base14[i] = base14[i - 1] * 13331;// base[i]=M^i
    }
}

void init24(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base24[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h24[i] = h24[i - 1] * 2333 + s[i];
        base24[i] = base24[i - 1] * 2333;// base[i]=M^i
    }
}
void init124(string s)//初始化哈希
{
    int n = s.size();
    s = "0" + s;//让其下标从1开始
    base124[0] = 1;
    for (int i = 1;i <= n;i++)
    {
        h124[i] = h124[i - 1] * 2333 + s[i];
        base124[i] = base124[i - 1] * 2333;// base[i]=M^i
    }
}


void check2() {
    string s1 = s[1][2];
    string s2 = s[2][1];
    int cnt1[33] = {0}, cnt2[33] = {0};
    for (int i = 0; i < s1.length(); i++) {
        cnt1[s1[i] - 'a']++;
    }
    for (int i = 0; i < s2.length(); i++) {
        cnt2[s2[i] - 'a']++;
    }
    for (int i = 0; i < 26; i++) {
        if (cnt1[i] != cnt2[i]) {
            cout << "NONE\n";
            return ;
        }
    }
    if(s1.length() != s2.length() || s1.length() == 1) {
        cout << "NONE\n";
        return;
    }   
    int len = s1.length();
    init(s1); init1(s2);init2(s1);init12(s2);
    init4(s1); init14(s2);init24(s1);init124(s2);
    int cnt = 0, pos;
    for(int i = 0; i < s1.length() - 1; i++) {
        // if(query(1, i + 1) == query1(len - i, len) && query2(1, i + 1) == query12(len - i, len) && query4(1, i + 1) == query14(len - i, len) && query24(1, i + 1) == query124(len - i, len)){
        //     cnt++; pos = i + 1;
        // }
        // if(cnt == 2) break;
        if(query(1, i + 1) == query1(len - i, len) && query(i + 2, len) == query1(1, len - i - 1)
        && query2(1, i + 1) == query12(len - i, len) && query2(i + 2, len) == query12(1, len - i - 1)
        && query4(1, i + 1) == query14(len - i, len) && query4(i + 2, len) == query14(1, len - i - 1)
        && query24(1, i + 1) == query124(len - i, len) && query24(i + 2, len) == query124(1, len - i - 1)){ 
            cnt++; pos = i + 1;
        }
        if(cnt == 2) break;
    }
    if(cnt == 0) {
        cout << "NONE\n";
    }
    else if(cnt == 2) {
        cout << "MANY\n";
    }
    else {
        cout << "UNIQUE\n";
        for(int i = 0; i < pos; i++) {
            cout << s1[i];
        }
        cout << '\n';
        for(int i = pos; i < s1.length(); i++) {
            cout << s1[i];
        }
        cout << '\n';
    }
}

void solve() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            cin >> s[i][j];
            l[i][j] = s[i][j].length();
        }
    }
    if (n == 2) {
       		int m = s[0][1].size();
		string S = s[0][1] + "#" + s[1][0];
		string T = s[1][0] + "#" + s[0][1];
		int sz = S.size();
		vector<int> fs(sz), ft(sz);
		int p = 0;
		for (int i = 1; i < sz; i++) {
			while (p != 0 && S[p] != S[i])
				p = fs[p - 1];
			
			if (S[p] == S[i]) fs[i] = ++p;
		}
		p = 0;
		for (int i = 1; i < sz; i++) {
			while (p != 0 && T[p] != T[i]) 
				p = ft[p - 1];
			
			if (T[p] == T[i]) ft[i] = ++p;
		}
		string ansA, ansB;
		bool found = false;
		vector<bool> chk(sz);
		for (int v = sz - 1; ; v = fs[v] - 1) {
			if (fs[v] == 0) break;
			chk[fs[v]] = true;
		}
		for (int v = sz - 1; ; v = ft[v] - 1) {
			if (ft[v] == 0) break;
			if (chk[m - ft[v]]) {
				if (found) { cout << "MANY"; return ; } 
				else {
					found = true;
					ansA = S.substr(0, m - ft[v]);
					ansB = T.substr(0, (int)ft[v]);
				}
			}
		}
		if (!found) {cout << "NONE"; return ;}
		else {
			cout << "UNIQUE\n";
			cout << ansA << '\n';
			cout << ansB << '\n';
		}
		return ;
    }
    for (int i = 1; i <= n; i++) {
        if (i == n) {
            m[i][n + 1] = l[2][3];
            m[i][2] = 1;
            m[i][3] = 1;
        }
        else {
            m[i][n + 1] = l[1][i + 1];
            m[i][1] = 1;
            m[i][i + 1] = 1;
        }
    }
    gauss();
    for (int i = 1; i <= n; i++) {
        if (ans[i] <= 0) con = 2;
    }
    // cout << con << '\n';
    if (con == 0) {
        if (run(ans[1])) {
            cout << "UNIQUE\n";
            for (int i = 1; i <= n; i++) {
                cout << AN[i] << '\n';
            }
        }
        else {
            cout << "NONE\n";
        }
    }
    else if (con == 2) {
        cout << "NONE\n";
    }
}

signed main() {
    io;
    int T = 1;
    //cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}