/* -*- coding: utf-8 -*-
 *
 * 2042.cc:  No.2042 RGB Caps - yukicoder
 */

#include<cstdio>
#include<algorithm>
#include<utility>
 
using namespace std;

/* constant */

const int MAX_N = 100000;
const char ccs[] = "RGB";

/* typedef */

typedef pair<int,int> pii;

/* global variables */

int cmap[128], cs[3];
pii acs[MAX_N];
char s[MAX_N + 4];

/* subroutines */

/* main */

int main() {
  for (int i = 0; ccs[i]; i++) cmap[ccs[i]] = i;

  int n, k;
  scanf("%d%d", &n, &k);

  for (int i = 0; i < k; i++) {
    int ai;
    char cis[4];
    scanf("%d%s", &ai, cis), ai--;
    acs[i] = pii(ai, cmap[cis[0]]);
  }
  sort(acs, acs + k);

  fill(cs, cs + 3, 0);
  for (int i = 0, j = 0; i < n; i++) {
    int mc = i / 3;
    if (j < k && acs[j].first == i) {
      int cj = acs[j++].second;
      for (int d = 0; d < 3; d++) {
	int cd = (cj + d) % 3;
	if (cs[cd] == mc) {
	  s[i] = ccs[cd];
	  cs[cd]++;
	  break;
	}
      }
    }
    else {
      for (int cd = 0; cd < 3; cd++)
	if (cs[cd] == mc) {
	  s[i] = ccs[cd];
	  cs[cd]++;
	  break;
	}
    }
  }

  puts(s);
  return 0;
}