Added day2 solution

Author: avidLearnerInProgress

30-days-of-code-may/02.jewelAndStones.cpp

@@ -0,0 +1,22 @@
+class Solution {
+public:
+    int numJewelsInStones(string J, string S) {
+        if(J.size() == 0 or S.size() == 0) return 0;
+        
+        map<char, int> stones;
+        
+        for(int i=0; i<S.size();i++){
+            if(stones.find(S[i]) == stones.end())
+                stones[S[i]] = 1;
+            else
+                stones[S[i]]++;
+        }
+        int c = 0;
+        for(char j:J){
+            if(stones.find(j) != stones.end()){
+                c+=stones[j];
+            }
+        }
+        return c;
+    }
+};