LeetCode零基础学习IDE环境（771.Jewels and Stones）_[leetcode从零开刷]771. jewels and stones-优快云博客

本文介绍了一种通过遍历字符串来判断哪些石头属于宝石的方法。输入两个字符串 J 和 S，分别代表宝石类型和拥有的石头，输出属于宝石的石头数量。代码采用双层循环匹配 J 中的每种宝石是否出现在 S 中。

Jewels and Stones

Description

You're given strings J representing the types of stones that are jewels, and S representing the stones you have. Each character inS 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".

Input: J = "aA", S = "aAAbbbb"
Output: 3

Input: J = "z", S = "ZZ"
Output: 0

Note:

S and J will consist of letters and have length at most 50.
The characters in J are distinct.

Solution

#include<iostream>
#include<string>
using namespace std;

class Solution {
public:

	int numJewelsInStones(string J, string S) {
		int result = 0;
		int jlen = J.length();
		int slen = S.length();
		for (int i = 0; i < slen; i++) {
			for (int j = 0; j < jlen; j++) {
				if (S[i] == J[j]) {
					result++;
					break;
				}
			}
		}
		return result;
	}
};


int main()
{

	Solution js;
	string Jewels = "aaaaA";
	string Stones = "AAAAbbbbbccc";
	int numss;
	numss = js.numJewelsInStones(Jewels, Stones);
	cout << "numss= " << numss << endl;

	system("pause");
	return 0;

}