Read an indefinite number of digits from a file, store in an array (no space)

Question

I want to read a file that contains this (example):

194920392038122341

and store each digit in an integer array. For instance, a[0] would be 1, a[1] would be 9, etc.

I tried using something like this to read the digits and store them in an array:

    int n = 0;

    vector<int> numbers; 



    ifstream in

    in.open("input.txt");



    while (in >> n)

    {

        numbers.push_back(n);

    }



    int* array = &numbers[0];

However, for some reason, this doesn't read the individual digits from the file. It reads them as "12", "34", "35" etc.

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Answer 1

Here's how I would do it:

char n = 0;
vector<int> numbers; 

ifstream in("input.txt");

while (in.get(n)) {
   if(std::isdigit(n) {
       numbers.push_back(n - '0');
   }
}

int* array = &numbers[0];

Read an indefinite number of digits from a file, store in an array (no space)

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