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access variable outside for loop/function

cloudEndeavor (5)
how do i access a variable initialized in a for loop or a function outside of it?
in the code below, i can only cout name inside of the for loop. how can i get it to
print name outside the loop?
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for (int i = 0; i < arraySize; i++)
    {   int firstComma, secondComma, thirdComma;
        string row = array[i];
        firstComma = row.find(",");
        int weight = stoi(row.substr(0, firstComma-1));
        secondComma = row.find(",", firstComma+1);
        string color = row.substr(firstComma+2, secondComma -1);
        string name = row.substr(secondComma+2);
        cout << name << endl;
    }
thmm (703)
Just declare name outside the for loop.
seeplus (6591)
weight, color and name can only be accessed within the loop. Often in cases like these you'd use a struct of the required elements and have it populated by the extract function. This struct would be defined outside of the loop. Or have a function that takes a std::string arg and parses it into a returned struct.

Consider (not tried):

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struct Extract {
    int weight {};
    std::string color;
    std::string name;
}:

Extract getData(const std::string& row) {
    const auto firstComma {row.find(",")};
    const auto secondComma {row.find(",", firstComma+1)};

    Extract data;

    data.weight = stoi(row.substr(0, firstComma-1));
    data.color = row.substr(firstComma+2, secondComma -1);
    data.name = row.substr(secondComma+2);
    return data;
}


Then if you want access to the last Extract from the array then:

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Extract data;

for (int i = 0; i < arraySize; ++i)
    data = getData(array[i]);


But often you'd have say a std::vector of Extract and populate the vector. Something like:

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std::vector<Extract> data;

for (int i = 0; i < arraySize; ++i)
    data.push_back(getData(array[i]));

// Use data here as required


Last edited on
cloudEndeavor (5)
thanks a lot. that was very helpful.
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