Jewels and Stones

Problem Statement

You're given strings jewels representing the types of stones that are jewels, and stones representing the stones you have. Each character in stones is a type of stone you have. You want to know how many of the stones you have are also jewels.

Letters are case sensitive, so "a" is considered a different type of stone from "A".

Examples

Example 1:

Input: jewels = "aA", stones = "aAAbbbb"
Output: 3

Example 2:

Input: jewels = "z", stones = "ZZ"
Output: 0

Constraints

• 1 <= jewels.length, stones.length <= 50
• jewels and stones consist of only English letters.
• All the characters of jewels are unique.

Approaches

1️⃣ Nested Loop

Code:

int numJewelsInStones(string jewels, string stones) {
        int count = 0;
        for(int i=0; i<jewels.length();i++){
            for(int j=0; j<stones.length();j++){
                if(jewels[i]==stones[j])
                    count++;
            }
        }
        return count;
    }

Complexity Analysis:

• Time complexity: O(m*n), m and n is the size of both strings
• Space complexity: O(1)