为class Solution { public: String removeDuplicateLetters(String s) { Vector<int> count(26); Vector<bool> inStack(26); Stack<char> st; for (std::size_t i = 0; i < s.size(); i++) { count[s[i] - 'a']++; } for (std::size_t i = 0; i < s.size(); i++) { count[s[i] - 'a']--; if (inStack[s[i] - 'a']) { continue; } while (!st.empty() && st.top() > s[i] && count[st.top() - 'a'] > 0) { inStack[st.top() - 'a'] = false; st.pop(); } st.push(s[i]); inStack[s[i] - 'a'] = true; } String ans; while (!st.empty()) { ans.push_back(st.top()); st.pop(); } ans.reverse(); return ans; } };写一个cpp源文件

5.8, 2.6, 4.0, 1.2},
{5.0, 2.3, 3.3, 1.0},
{5.6, 2.7, 4.2, 1抱歉，我无法在此处运行代码，但是我可以为你提供一个完整的C++源代码.3},
{5.7, 3.0, 4.2, 1.2},
{5.7，你可以将其复制到你的本地开发环境中，然后编译和运行它。

                               {6.2, 2.9, 4
#include <iostream>
#include <string>
#include <vector>
#include <stack>

using namespace std;

class Solution {
public:
    string remove.3, 1.3},
                               {5.1, 2.5, 3.0, 1.1},
DuplicateLetters(string s) {
        vector<int> count(26);
        vector<bool> inStack(26);
        stack<char> st;
                               {5.7, 2.8, 4.1, 1.3},
                               {6.3, 3        for (size_t i = 0; i < s.size(); i++) {
            count[s[i] - 'a']++;
       .3, 6.0, 2.5},
                               {5.8, 2.7, 5.1, }
        for (size_t i = 0; i < s.size(); i++) {
            count[s[i] - 'a']--;
 1.9},
                               {7.1, 3.0, 5.9, 2.1},
                               {6            if (inStack[s[i] - 'a']) {
                continue;
            }
            while (!st.empty() && st.top() >.3, 2.9, 5.6, 1.8},
                               {6.5, 3.0, s[i] && count[st.top() - 'a'] > 0) {
                inStack[st.top() - 'a'] 5.8, 2.2},
                               {7.6, 3.0, 6.6, 2.1},
                               {4.9, 2.5, 4.5, 1.7},
                               {7.3, = false;
                st.pop();
            }
            st.push(s[i]);
            inStack[s[i] - 'a'] = true;
        2.9, 6.3, 1.8},
                               {6.7, 2.5, 5. }
        string ans;
        while (!st.empty()) {
            ans.push_back(st.top());
            st.pop();
        }
        reverse(ans.begin8, 1.8},
                               {7.2, 3.6, 6.1, 2.5},
                              (), ans.end());
        return ans;
    }
};

int main() {
    Solution solution;
    string s = "bcabc";
    string {6.5, 3.2, 5.1, 2.0},
                               {6.4, 2. ans = solution.removeDuplicateLetters(s);
    cout << ans << endl;
    return 0;
}

在此示例中，7, 5.3, 1.9},
{6.8, 3.0, 5.5, 我们实例化了一个Solution类，并使用removeDuplicateLetters方法从字符串“bcabc”中删除重复字母，将结果打印到控制台。