#include "bits/stdc++.h"
using namespace std;
#define int long long
#define REP(i, n) for (int i = 0; i < (int)n; ++i)
#define RREP(i, n) for (int i = (int)n - 1; i >= 0; --i)
#define FOR(i, s, n) for (int i = s; i < (int)n; ++i)
#define RFOR(i, s, n) for (int i = (int)n - 1; i >= s; --i)
#define ALL(a) a.begin(), a.end()
#define IN(a, x, b) (a <= x && x < b)
template<class T>inline void out(T t){cout << t << "\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout << t << " ";out(ts...);}
template<class T>inline bool CHMIN(T&a,T b){if(a > b){a = b;return true;}return false;}
template<class T>inline bool CHMAX(T&a,T b){if(a < b){a = b;return true;}return false;}
constexpr int INF = 1e18;



signed main(){
	int N,K;
	cin >> N >> K;
	vector<tuple<string,int>>v(N);
	int ans = INF;
	REP(i,N){
		string s;
		int c;
		cin >> s >> c;
		v[i] = {s,c};
		int J = 0,O = 0,I = 0;
		REP(j,s.size()){
			if(s[j] == 'J')++J;
			if(J >= K && s[j] == 'O')++O;
			if(O >= K && s[j] == 'I')++I;
		}
		if(I >= K)CHMIN(ans,c);
	}
	vector<int>dp1(K + 100,INF);
	dp1[0] = 0;
	REP(i,N){
		auto[s,c] = v[i];
		int cnt = 0;
		REP(j,s.size()){
			if(s[j] == 'J')++cnt;
		}
		REP(j,K){
			CHMIN(dp1[j + cnt],dp1[j] + c);
		}
	}
	RREP(i,K + 99)CHMIN(dp1[i],dp1[i + 1]);
	vector<int>dp2(K + 100,INF);
	dp2[0] = dp1[K];
	REP(i,N){
		int jj = 0,o = 0;
		auto[s,c] = v[i];
		REP(j,s.size()){
			if(s[j] == 'O')++o;
		}
		REP(j,s.size()){
			if(s[j] == 'J')++jj;
			else if(s[j] == 'O')--o;
			if(K - jj >= 0)CHMIN(dp2[o],dp1[K - jj] + c);
		}
	}
	REP(i,N){
		auto[s,c] = v[i];
		int cnt = 0;
		REP(j,s.size()){
			if(s[j] == 'O')++cnt;
		}
		REP(j,K){
			CHMIN(dp2[j + cnt],dp2[j] + c);
		}
	}
	RREP(i,K + 99)CHMIN(dp2[i],dp2[i + 1]);
	vector<int>dp3(K + 100,INF);
	dp3[0] = dp2[K];
	REP(i,N){
		int o = 0,ii = 0;
		auto[s,c] = v[i];
		REP(j,s.size()){
			if(s[j] == 'I')++ii;
		}
		REP(j,s.size()){
			if(s[j] == 'O')++o;
			else if(s[j] == 'I')--ii;
			if(K - o >= 0)CHMIN(dp3[ii],dp2[K - o] + c);
		}
	}
	REP(i,N){
		auto[s,c] = v[i];
		int cnt = 0;
		REP(j,s.size()){
			if(s[j] == 'I')++cnt;
		}
		REP(j,K){
			CHMIN(dp3[j + cnt],dp3[j] + c);
		}
	}
	RREP(i,K + 99)CHMIN(dp3[i],dp3[i + 1]);
	if(dp3[K] == INF)out(-1);
	else out(min(ans,dp3[K]));
	//REP(i,K + 1)out(i,dp1[i],dp2[i],dp3[i]);
}