import sys
input = sys.stdin.readline

N,K=map(int,input().split())

S=[input().split() for i in range(N)]

DP=[1<<63]*(3*K+2+100)
DP[0]=0

T=["J"]*K+["O"]*K+["I"]*K

J=[]
O=[]
I=[]
for s,M in S:
    J.append((s.count("J"),int(M)))
    O.append((s.count("O"),int(M)))
    I.append((s.count("I"),int(M)))

from fractions import Fraction

MAXJ=max(J,key=lambda x:Fraction(x[0],x[1]))
MAXO=max(O,key=lambda x:Fraction(x[0],x[1]))
MAXI=max(I,key=lambda x:Fraction(x[0],x[1]))
    

for i in range(3*K):
    #NEXT=T[i:i+80]

    if i<K-500:
        if DP[i]==1<<63:
            continue
        else:
            DP[i+MAXJ[0]]=DP[i]+MAXJ[1]

    elif K+100<i<K*2-500:
        if DP[i]==1<<63:
            continue
        else:
            DP[i+MAXO[0]]=DP[i]+MAXO[1]
            
    elif K*2+100<i<K*3-500:
        if DP[i]==1<<63:
            continue
        else:
            DP[i+MAXI[0]]=DP[i]+MAXI[1]

    else:
        for j in range(N):
            ind=0
            M=int(S[j][1])
            for s in S[j][0]:
                if i+ind<3*K and s==T[i+ind]:
                    ind+=1
                    DP[i+ind]=min(DP[i+ind],DP[i]+M)

if 1<<63==DP[K*3]:
    print(-1)
else:
    print(DP[K*3])