#include <cstdio>
#include <algorithm>
#include <vector>
#include <cstring>
using namespace std;
const int N = 1e5 + 5, mod = 998244353;
int n;
char s[N];
long long f[2][65][8], ans;
inline void add (long long &a, long long b) {a = ((a + b >= mod) ? a + b - mod : a + b);}
int main() {
    scanf ("%d", &n);
    scanf ("%s", s + 1);
    f[0][0][0] = 1;
    for (int i = 1, t = 1; i <= n; i++, t ^= 1) {
        memset(f[t], 0, sizeof(f[t]));
        for (int j = 0; j <= 62; j++) for (int k = 0; k < 8; k++) {
            if ('0' <= s[i] && s[i] <= '9') add(f[t][s[i] - '0' + 1][k | 1], f[t ^ 1][j][k]);
            else if ('A' <= s[i] && s[i] <= 'Z') add(f[t][s[i] - 'A' + 11][k | 2], f[t ^ 1][j][k]);
            else if ('a' <= s[i] && s[i] <= 'z') {
                if (s[i] - 'A' + 11 != j) add(f[t][s[i] - 'A' + 11][k | 2], f[t ^ 1][j][k]);
                if (s[i] - 'A' + 37 != j) add(f[t][s[i] - 'a' + 37][k | 4], f[t ^ 1][j][k]);
            } else {
                for (int p = 1; p <= 62; p++) if (p != j) {
                    if (p <= 10) add(f[t][p][k | 1], f[t ^ 1][j][k]);
                    else if (p <= 36) add(f[t][p][k | 2], f[t ^ 1][j][k]);
                    else add(f[t][p][k | 4], f[t ^ 1][j][k]);
                }
            }
        }
    }   
    for (int j = 1; j <= 62; j++) add(ans, f[n & 1][j][7]);
    printf ("%lld\n", ans);
    return 0;
}