#include <bits/stdc++.h>
 
using namespace std;
 
#define DEBUG(x) cerr<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cerr<<#v<<":";for(int i=0;i<v.size();i++) cerr<<" "<<v[i]; cerr<<endl;
#define DEBUG_MAT(v) cerr<<#v<<endl;for(int i=0;i<v.size();i++){for(int j=0;j<v[i].size();j++) {cerr<<v[i][j]<<" ";}cerr<<endl;}
typedef long long ll;
#define int ll
 
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
template<class S, class T> pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first + t.first, s.second + t.second); }
template<class S, class T> pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template<class S, class T> ostream& operator<<(ostream& os, pair<S, T> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
#define X first
#define Y second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define rrep1(i,n) for(int i=(int)(n);i>0;i--)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(),c.end()
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl;
//int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
//int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {1, 0, -1, 0}, dy = {0, 1, 0, -1};
vi dx2 = { 1,1,0,-1,-1,-1,0,1 }, dy2 = { 0,1,1,1,0,-1,-1,-1 };
#define fio() cin.tie(0); ios::sync_with_stdio(false);
//const ll MOD = 1000000007;
const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'

int n, k;
const int N = 82;
vector<string> s;
vl c;
vii J(N), O(N), I(N);

vll calc_dp(vii num) {
    vll dp(n + 1, vl(k + 82, INF));
    dp[0][0] = 0;
    rep1 (i, n) {
        rep (j, k + 82) {
            chmin(dp[i][j], dp[i - 1][j]);
            if (num[i - 1].back() > 0 and j - num[i - 1].back() >= 0) {
                chmin(dp[i][j], dp[i - 1][j - num[i - 1].back()] + c[i - 1]);
                chmin(dp[i][j], dp[i][j - num[i - 1].back()] + c[i - 1]);
            }
        }
    }
    ll mi = INF;
    rrep (j, k + 82) {
        chmin(mi, dp[n][j]);
        dp[n][j] = mi;
    }
    return dp;
}

bool only_one(string s) {
    string tar = "JOI";
    int j = 0;
    int cnt = 0;
    rep (i, s.size()) {
        if (s[i] == tar[j]) {
            cnt++;
            if (cnt == k) {
                cnt = 0;
                j++;
                if (j == 3) break;
            }
        }
    }
    return j == 3;
}

signed main() {
    fio();
    
    cin >> n >> k;
    s.resize(n);
    c.resize(n);

    bool flagI = false, flagJ = false, flagO = false;
    rep (i, n) {
        cin >> s[i] >> c[i];
        rep (j, s[i].size()) {
            if (s[i][j] == 'J') flagJ = true;
            else if (s[i][j] == 'O') flagO = true;
            else flagI = true;
        }
    }
    if (not flagI or not flagJ or not flagO) {
        cout << -1 << endl;
        return 0;
    }

    rep (i, n) {
        J[i].resize(s[i].size() + 1);
        O[i].resize(s[i].size() + 1);
        I[i].resize(s[i].size() + 1);
        for (int j = 0; j < s[i].size(); j++) {
            J[i][j + 1] += J[i][j];
            O[i][j + 1] += O[i][j];
            I[i][j + 1] += I[i][j];
            if (s[i][j] == 'J') J[i][j + 1]++;
            else if (s[i][j] == 'O') O[i][j + 1]++;
            else I[i][j + 1]++;
        }
    }
    // DEBUG_MAT(J);
    // DEBUG_MAT(O);
    // DEBUG_MAT(I);

    vll dpj = calc_dp(J);
    vll dpo = calc_dp(O);
    vll dpi = calc_dp(I);

    // DEBUG_MAT(dpj);
    // DEBUG_MAT(dpo);
    // DEBUG_MAT(dpi);

    ll mi = INF;
    rep (i, n) {
        if (only_one(s[i])) chmin(mi, c[i]);
    }

    rep (i, n) {
        for (int j = 0; j <= s[i].size(); j++) {
            for (int l = j + 1; l <= s[i].size(); l++) {
                if (O[i][l] - O[i][j] < k) continue;
                ll ans = c[i];
                ll fu_J = max(0LL, k - J[i][j]);
                ll fu_I = max(0LL, k - (I[i].back() - I[i][l]));
                ans += dpj[n][fu_J] + dpi[n][fu_I];
                chmin(mi, ans);
            }
        }
    }

    rep (i, n) {
        for (int j = 0; j <= s[i].size(); j++) {
            rep (l, n) {
                for (int m = 0; m <= s[l].size(); m++) {
                    ll ans = c[i] + c[l];
                    ll fu_J = max(0LL, k - J[i][j]);
                    ll fu_O = max(0LL, k - (O[i].back() - O[i][j]) - O[l][m]);
                    ll fu_I = max(0LL, k - (I[l].back() - I[l][m]));
                    ans += dpj[n][fu_J] + dpo[n][fu_O] + dpi[n][fu_I];
                    chmin(mi, ans);
                }
            }
        }
    }
    cout << mi << endl;
}