#include <bits/stdc++.h>
using namespace std;
int n,m;
char chair[200]={};

void A(char ch){
  int i=1;
  while(chair[i]!='#') i++;
  chair[i]=ch;
}

void B(){
  int i=n;
  while(chair[i]!='#')i--;
  chair[i]='B';
}

void C(int kai){
  if(kai==0){
    if(n%2)chair[(n+1)/2]='C';
    else chair[n/2+1]='C';
    return;
  }
  for(int i=1;i<=n;i++){
    if(chair[i]=='#')continue;
    if(chair[i+1]=='#') chair[i+1]='C',i=n;
    if(chair[i-1]=='#') chair[i-1]='C',i=n;
   
  }
}

void D(int kai){
  int R=0,L=0;
  while(chair[n-R]=='#')R++;
  while(chair[L+1]=='#') L++;
  
  int M=0,idx=0,cnt=0;
  for(int i=1;i<=n;i++){
    if(chair[i]=='#')cnt++;
    else cnt=0;
    if(M+M%2<cnt) M=cnt,idx=i;
  }
  if(M<=2&&L<=1&&R<=1) {
    A('D');
    return;
  }
  cout <<L<<" "<<M<<" "<<R<<endl;
  if(L-1>=(M-1)/2&&L-1>=R-1)chair[1]='D';
  else if(R-1>=(M-1)/2)chair[n]='D';
  else chair[idx-M+1+(M-1)/2]='D';

}

int main(){

  while(1){
    cin>>n>>m;
    if(!n&&!m)break;
    for(int i=0;i<=130;i++) chair[i]='#';
    chair[0]=chair[n+1]=0;
    for(int i=0;i<m;i++){
      char a;
      cin>>a;
      if(a=='A') A(a);
      if(a=='B') B();
      if(a=='C') C(i);
      if(a=='D') D(i);
    }
    printf("%s\n",chair+1);
  }
  return 0;
}