Fifth algorithm-Gem and stone algorithm

2. Topic

   The given string J represents the type of gem in the stone, and S the string represents the stone you own.  SEach character represents a type of stone you have, and you want to know how many of the stones you have are gems. The J letters in are not repeated, J and all the S characters in are letters. Letters are case-sensitive, so "a" and "A" are different types of stones.

4. Analysis
   Give two strings, comparing the number of repetitions of a string in the data in another string

   • Requirements:
     Case-sensitive letters
     Total number of claims

6. Test data
   Input: J = "aA", S = "aAAbbbb" output: 3
   Input: J = "z", S = "ZZ" output: 0

8. Reference answer
   Algorithm idea:

   • First, we find the number of stones in s that are repeated in the array
   • The traversal data is compared with the characters in J.

   • public int Numjewelsinstones (string J, String S) {
         int count = 0;
         map<string,integer> map =  new hashmap<string,integer> ();
         for (int i =0;i<s.length (); i++) {
             String SV = string.valueof (S.charat (i));
             if (Map.containskey (SV)) {
                 Map.put (Sv,map.get (SV) +1);
             }else{
                 Map.put (sv,1);
             }
         }
     
         for (int i =0;i<j.length (); i++) {
     
             Char s =j.charat (i);
             Count=map.get (string.valueof (s)) ==null?0+count:map.get (string.valueof (s)) +count;
         }
         return count;
     }

5, Excellent solution

　　　　　　　　

Class Solution {
public int Numjewelsinstones (string J, String S) {
int result = 0;
Char[] s = new char[128];
for (char C:s.tochararray ()) {
s[c]++;
}
for (char J:j.tochararray ()) {
Result + = S[j];
}
return result;
}
}

Fifth algorithm-Gem and stone algorithm