#include <set>
#include <string>
 
std::set<char> findRepeatedChars(const std::string& text) {
    std::set<char> seen;
    std::set<char> repeated;
 
    for (size_t i = 0; i < text.size(); ++i) {
        char ch = text[i];
        // If already seen, it's a repeated character
        if (seen.find(ch) != seen.end()) {
            repeated.insert(ch);
        } else {
            seen.insert(ch);
        }
    }
 
    return repeated;
}
int main(void){
 
}

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