#include <algorithm>
    #include <string>
    #include <iostream>
    #include <vector>
 
    size_t vec_char_count(const std::vector<std::string>& vec, char c) {
        size_t count = 0;
        for (auto& str : vec) {
            count += std::count(str.begin(), str.end(), c);
        }
        return count;
    }
 
    int main() {
        std::vector<std::string> vec {
            "hello\nworld\n",
            "pizza\n"
        };
        std::cout << vec_char_count(vec, '\n') << "\n";
    }
 

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