#include <fstream>
#include <cstring>
#include <vector>
using namespace std;
const int maxn = 1e4+10, alphabet = 256;

ifstream fin("printing.in");
ofstream fout("printing.out");

int n, a, b, m, d, h;
int unkeep[maxn];
string s;
vector < char > v;
int where[alphabet];

void solve() {

    memset(where, -1, sizeof(where));

    for (int i = 1 ; i <= n ; ++i) {

        if (where[s[i]] != -1) continue;
        v.push_back(s[i]);
        where[s[i]] = v.size()-1;

    }

    fout << v.size() << '\n';
    for (char c : v)
        fout << c << '\n';

    int cnt = 1, instruct_cnt = 0;

    for (int i = 2 ; i <= n ; ++i) {

        if (s[i] == s[i-1]) ++cnt;
        else {

            instruct_cnt += 2;
            cnt = 1;

        }

    }

    instruct_cnt += 1;
    fout << instruct_cnt << '\n';

    cnt = 1;

    for (int i = 2 ; i <= n ; ++i) {

        if (s[i] == s[i-1]) ++cnt;
        else {

            fout << "w " << cnt << '\n';
            fout << "cd " << where[s[i]]+1 << '\n';
            cnt = 1;

        }

    }

    fout << "w " << cnt << '\n';

}

void fast_io() {

    ios_base :: sync_with_stdio(0);
    fin.tie(nullptr);
    fout.tie(nullptr);

}

void read() {

    fin >> n;
    fin >> s;
    s = ' ' + s;

    for (int i = 1 ; i <= 27 ; ++i)
        fin >> unkeep[i];

}

int main () {

    fast_io();
    read();
    solve();

    return 0;

}