classSolution{public:intminNumberOfFrogs(string croakOfFrogs){int c =0, r =0, o =0, a =0, k =0, ans =0;for(char x : croakOfFrogs){if(x =='c') c +=1;elseif(x =='r') r +=1;elseif(x =='o') o +=1;elseif(x =='a') a +=1;elseif(x =='k') k +=1;elsereturn-1;if(r > c or o > r or a > o or k > a)return-1;
ans =max(c, ans);if(k ==1){
c -=1;
r -=1;
o -=1;
a -=1;
k -=1;}}if(c)return-1;return ans;}};
classSolution{int at[10];public:intminNumberOfFrogs(string croakOfFrogs){int l = croakOfFrogs.length();memset(at,0,sizeof(at));for(char c: croakOfFrogs){int cur;if(c =='c') cur =0;elseif(c =='r') cur =1;elseif(c =='o') cur =2;elseif(c =='a') cur =3;elseif(c =='k') cur =4;if(cur ==0){if(at[4]>0)--at[4];++at[0];}else{if(!at[cur -1])return-1;--at[cur -1],++at[cur];}}for(int i =0; i <4;++i)if(at[i]>0)return-1;return at[4];}};