#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")
using namespace std;
const int N = 1e5 + 5; 

int n, m, d; char s[N];
int dfn[N], low[N], num, st[N], tot;
bool ins[N], flag;
vector<int> G[N];
int col[N], cnt;

inline void tarjan(int x) {
    dfn[x] = low[x] = ++num; ins[st[++tot] = x] = 1; 
    for (int y : G[x]) 
        if (!dfn[y]) tarjan(y), low[x] = min(low[x], low[y]);
        else if (ins[y]) low[x] = min(low[x], dfn[y]);
    if (low[x] == dfn[x]) {
        ++cnt; int y;
        do ins[y = st[tot--]] = 0, col[y] = cnt; while (x != y); 
    }
}

int a[N], b[N]; char x[N], y[N];
int pos[10]; char val[10]; bool c[3][3]; // 当不允许使用 i 时，使用了 i+1 为真，否则为假
inline bool solve(void) {
    num = tot = cnt = 0; 
    for (int i = 1; i <= n << 1; ++i) dfn[i] = ins[i] = 0, G[i].clear();
    for (int i = 1; i <= d; ++i) s[pos[i]] = val[i];
    for (int i = 1; i <= m; ++i) {
        if (s[a[i]] == x[i]) continue;
        bool p = c[s[a[i]] - 'A'][x[i] - 'A'], q = c[s[b[i]] - 'A'][y[i] - 'A'];
        if (s[b[i]] == y[i]) { 
            G[a[i] + (!p) * n].emplace_back(a[i] + p * n);
            continue; 
        }
        G[a[i] + (!p) * n].emplace_back(b[i] + (!q) * n);
        G[b[i] + q * n].emplace_back(a[i] + p * n);
    }
    // for (int i = 1; i <= n << 1; ++i) if (!dfn[i]) tarjan(i);
    for (int i = 1; i <= n; ++i) {
        if (!dfn[i]) tarjan(i); 
        if (!dfn[i + n]) tarjan(i + n); 
        if (col[i] == col[i + n]) return 0;
    }
    for (int i = 1; i <= n; ++i) cout << char((s[i] - 'A' + (col[i + n] > col[i] ? 1 : 2)) % 3 + 'A'); 
    return cout << "\n", 1; 
}

inline void dfs(int x) {
    if (flag) return; if (x > d) return flag = solve(), void(); 
    val[x] = 'A'; dfs(x + 1); 
    val[x] = 'B'; dfs(x + 1); 
}

int main(void) {
    ios::sync_with_stdio(0); cin.tie(0); 
    cin >> n >> d >> s + 1 >> m; d = 0; c[0][1] = c[1][2] = c[2][0] = 1; 
    for (int i = 1; i <= n; ++i) { s[i] -= 32; if (s[i] == 'X') pos[++d] = i; }
    for (int i = 1; i <= m; ++i) cin >> a[i] >> x[i] >> b[i] >> y[i]; 
    dfs(1); if (!flag) cout << "-1\n"; return 0; 
}