You're given strings J
representing the types of stones that are jewels, and S
representing the stones you have. Each character in S
is a type of stone you have. You want to know how many of the stones you have are also jewels.
The letters in J
are guaranteed distinct, and all characters in J
and S
are letters. Letters are case sensitive, so "a"
is considered a different type of stone from "A"
.
Example 1:
Input: J = "aA", S = "aAAbbbb"
Output: 3
Example 2:
Input: J = "z", S = "ZZ"
Output: 0
Note:
S
andJ
will consist of letters and have length at most 50.- The characters in
J
are distinct.
题解:
class Solution {
public:
int numJewelsInStones(string J, string S) {
int j = J.size();
int s = S.size();
if (j == 0 || s == 0) {
return 0;
}
int ans = 0;
map<char, bool> dic;
for (int i = 0; i < j; i++) {
dic.insert(pair<char, bool>(J[i], true));
}
for (int i = 0; i < s; i++) {
if (dic.find(S[i]) != dic.end()) {
ans++;
}
}
return ans;
}
};