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#include <iostream>
#include <vector>
#include <set>
#include <string>
#include <numeric>

using namespace std;

string FoldWithMinus(string left, string right) {
    return left + " -"s + right;
}

string AddStopWords(const string& query, const set<string>& stop_words) {
    return query + std::accumulate(stop_words.begin(), stop_words.end(), ""s, FoldWithMinus);
}