#include <vector>
    #include <cstdlib>
 
    using Individual = std::vector<int>;
    using Population = std::vector<Individual>;
    // short for std::vector<std::vector<int>>;
 
    const size_t number_of_variables = 8;
 
    int main() {
        Population population(10);
 
        for (auto& individual : population) {
            individual.resize(number_of_variables);
            for (size_t j = 0; j < number_of_variables; ++j) {
                individual[j] = j;  // replace with random number
            }
        }
    }
 

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