#pragma warning(disable:4996)
#include"bits/stdc++.h"
using namespace std;
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)
#define RE assert(0);
const long long inf = 1e17;
string s[82]; int c[82]; int n, K;
int l[3][82];
int dp[3][83][100200];//dp[文字i][j種類][今k文字]
int rwa[3][82][82];

void memo() {
	rep(i, 3)rep(j, n + 1)rep(k, 100200)dp[i][j][k] = inf;

	rep(i, 3) {
		dp[i][0][0] = 0;
		rep(j, n) {
			rep(k, 100105) {
				dp[i][j + 1][k] = dp[i][j][k];
				if (k >= l[i][j]) dp[i][j + 1][k] = min(dp[i][j + 1][k], dp[i][j + 1][k - l[i][j]] + c[j]);
			}
		}
		for (int k = 100100; k >= 0; k--)dp[i][n][k] = min(dp[i][n][k], dp[i][n][k + 1]);
	}
}

signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> n >> K;
	if (n < 1 || n>80 || K < 1 || K>100000)RE;
	int ej = 0, eo = 0, ei = 0;
	rep(i, n) {
		cin >> s[i] >> c[i];
		if (c[i] < 0 || c[i]>1000000000)RE;
		if (s[i].size() < 0 || s[i].size() > 80)RE;
		rep(j, s[i].size()) {
			if (s[i][j] == 'J') {
				l[0][i]++;
				rwa[0][i][j + 1]++;
			}
			else if (s[i][j] == 'O') {
				l[1][i]++;
				rwa[1][i][j + 1]++;
			}
			else if (s[i][j] == 'I') {
				l[2][i]++;
				rwa[2][i][j + 1]++;
			}
			else RE;
		}
		ej += l[0][i]; eo += l[1][i]; ei += l[2][i];
		rep(j, s[i].size()) {
			rep(k, 3) {
				rwa[k][i][j + 1] += rwa[k][i][j];
			}
		}
	}
	if (!ej || !eo || !ei) {
		cout << -1 << endl; return 0;
	}
	memo();
	int ans = inf;
	rep(i, n) {//文字列1個
		rep(j, s[i].size()) {
			for (int k = j; k < s[i].size(); k++) {
				if (rwa[1][i][k + 1] - rwa[1][i][j] < K)continue;
				int jr = max(0ll, K - rwa[0][i][j]);
				int ji = max(0ll, K - rwa[2][i][s[i].size()] + rwa[2][i][k + 1]);
				ans = min(ans, c[i] + dp[0][n][jr] + dp[2][n][ji]);
			}
		}
	}
	rep(i, n) {
		rep(j, n) {//文字列2個
			rep(k, s[i].size() + 1) {
				rep(l, s[j].size() + 1) {
					int jr = max(0ll, K - rwa[0][i][k]);
					int jo = max(0ll, K - rwa[1][i][s[i].size()] + rwa[1][i][k] - rwa[1][j][l]);
					int ji = max(0ll, K - rwa[2][j][s[j].size()] + rwa[2][j][l]);
					ans = min(ans, c[i] + c[j] + dp[0][n][jr] + dp[1][n][jo] + dp[2][n][ji]);
				}
			}
		}
	}
	cout << ans << endl;
}