#include <bits/stdc++.h>
using namespace std;

void dbg_out() { cerr << endl; }
template<typename Head, typename... Tail>
void dbg_out(Head H, Tail... T) { cerr << ' ' << H; dbg_out(T...); }
#define dbg(...) cerr << "(" << #__VA_ARGS__ << ")", dbg_out(__VA_ARGS__)

#define int long long

const int MOD = 1e9 + 7;
const int INF = LLONG_MAX >> 1;

void solve() {
    int n, k; cin >> n >> k;
    pair<int, int> a[k];

    for (int i = 0; i < k; i++) {
        int x; cin >> x;
        char c; cin >> c;
        int y;
        if (c == 'R') y = 0;
        if (c == 'G') y = 1;
        if (c == 'B') y = 2;
        a[i] = {x, y};
    }

    sort(a, a + k);

    vector<int> ans(n);

    for (int i = 0; i < n; i++) {
        ans[i] = i % 3;
    }

    for (int i = 0; i < k; i++) {
        auto &[x, y] = a[i];
        int k = (x - 1) / 3 * 3, ind = -1;
        bool ok = false;
        for (int l = k; l < min(k + 3, n); l++) {
            if (ans[l] == y) {
                ind = l;
                ok = true;
                break;
            }
        }

        if (!ok) {
            ans[x - 1] = y;
        } else {
            swap(ans[x - 1], ans[ind]);
        }
    }

    for (int i = 0; i < n; i++) {
        if (ans[i] == 0) cout << 'R';
        if (ans[i] == 1) cout << 'G';
        if (ans[i] == 2) cout << 'B';
    }
    cout << '\n';
}

int32_t main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int tc = 1;
    // cin >> tc;

    while (tc--)  solve();
}