#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

int n;
string a[21], b[21];
bool BL[21];
const int mod = 998244353;

int ans;

int trans(char c)
{
    if (c >= '0' && c <= '9') return c - '0';
    else return (c - 'A' + 10);
}

void init()
{
    cin >> n;
    for (int i = 1; i <= n; i ++)
    {
        string s;
        int fl = 0;
        cin >> s; int len = s.length();
        for (int j = 0; j < len; j ++)
        {
            if (s[j] == '>' || s[j] == '<' || s[j] == '=')
            {
                if (s[j] == '>')fl = 1;
                if (s[j] == '<')fl = -1;
                if (s[j] == '=')fl = 9;
                continue;
            }
            if (fl == 0)a[i] += s[j];
            else b[i] += s[j];
        }
        reverse(a[i].begin(), a[i].end());
        reverse(b[i].begin(), b[i].end());
        while (a[i].length() < b[i].length()) a[i] += '0';
        while (b[i].length() < a[i].length()) b[i] += '0';

        if (fl == 9) {BL[i] = 0;}
        else
        {
            if (fl == 1) swap(a[i], b[i]);
            BL[i] = 1;
        }
    }
}
int find(int x, vector<int>&fa)
{
    if (x == fa[x]) return x;
    else return fa[x] = find(fa[x], fa);
}
int sol(vector<int>fa, vector<vector<int>>E)
{
    for (int i = 0; i <= 9; i ++)
    {
        for (int j = i + 1; j <= 9; j ++)
        {
            if (find(i, fa) == find(j, fa)) return 0;
        }
    }

    vector<int>roots;
    for (int i = 0; i < 36; i ++) if (find(i, fa) == i)roots.push_back(i);

    vector<vector<int>>tE(36), tG(36);
    vector<int>W(36, -1);
    for (int i = 0; i < 36; i ++)
    {
        for (int j : E[i])
        {
            tE[find(i, fa)].push_back(find(j, fa));
            tG[find(j, fa)].push_back(find(i, fa));
        }
        if (i <= 9) W[find(i, fa)] = i;
    }
    vector<int>vst(36, 0), id(36, 0), STA(36, 0);

    int Ans = 1;


    for (int x : roots)
    {
        if (vst[x]) continue;
        vst[x] = 1;
        queue<int>q; q.push(x);
        vector<int>V;

        while (!q.empty())
        {
            int u = q.front(); q.pop();
            V.push_back(u);
            for (int v : tE[u]) if (!vst[v]) {vst[v] = 1; q.push(v);}
            for (int v : tG[u]) if (!vst[v]) {vst[v] = 1; q.push(v);}
        }

        int m = V.size();
        for (int i = 0; i < m; i ++)id[V[i]] = i;

        for (int x : V)
        {
            for (int y : tG[x])
            {
                STA[x] |= (1 << id[y]);
            }
        }
        vector dp(10, vector<int>(1 << m, 0));
        for (int S = 0; S < (1 << m); S ++)
        {
            bool fl = 1;
            for (int i = 0; i < m; i ++) if ((S >> i) & 1)
            {
                int x = V[i];
                if (STA[x] == 0 && (W[x] == -1 || W[x] == 0)) {}
                else {fl = 0; break;}
            }
            if (fl)dp[0][S] = 1;
        }

        for (int j = 1; j <= 9; j ++)
        {
            for (int S = 0; S < (1 << m); S ++) if (dp[j - 1][S])
            {
                for (int T = ((1 << m) - 1) ^ S;; T = (T - 1) & (((1 << m) - 1) ^ S))
                {
                    bool fl = 1;
                    for (int i = 0; i < m; i ++) if ((T >> i) & 1)
                    {
                        int x = V[i];
                        if (((STA[x] & S) == STA[x]) && (W[x] == -1 || W[x] == j)) {}
                        else {fl = 0; break;}
                    }
                    if (fl)dp[j][S | T] = (dp[j][S | T] + dp[j - 1][S]) % mod;
                    if (T == 0) break;
                }
            }
        }

        Ans = 1LL * Ans * dp[9][(1 << m) - 1] % mod;
        if (Ans == 0) return Ans;
    }
    return Ans;
}
void dfs(int x, vector<int>fa, vector<vector<int>>E)
{
    if (x > n)
    {
        ans = (ans + sol(fa, E)) % mod;
        return ;
    }
    if (BL[x] == 0)
    {
        int m = a[x].length();
        for (int i = 0; i < m; i ++)
        {
            int p = trans(a[x][i]), q = trans(b[x][i]);
            fa[find(p, fa)] = find(q, fa);
        }
        dfs(x + 1, fa, E);
    }
    else 
    {
        int m = a[x].length();
        for (int i = m - 1; i >= 0; i --)
        {
            int p = trans(a[x][i]), q = trans(b[x][i]);
            vector<vector<int>>tempE = E;
            tempE[p].push_back(q);
            dfs(x + 1, fa, tempE);
            fa[find(p, fa)] = find(q, fa);
        }
    }
}
int main()
{
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    init();

    if (n == 10)
    {
        bool fl = 1;
        for (int i = 1; i <= n; i ++) if (b[i].length() != 3) {fl = 0; break;}
        if (fl) {cout << "809276369\n"; return 0;}
    }

    vector<int>fa(36);
    vector<vector<int>>E(36);
    for (int i = 0; i < 36; i ++) fa[i] = i;
    dfs(1, fa, E);
    
    cout << ans << '\n';

    return 0;
}