Question

Write a C++ that read a list of numbers from a .txt file into array. The first digit on the list will be array size, while the second number on the list will be our first number in our array list.

Example: t1.txt file contain list off input number: 5, 3, 6, 10, 43, 23. notice the first number is 5 which will need to be use as an array size and the rest of the numbers are in the array. While using dynamic array without using vector.

so file program should be read as array has limit of 5 numbers and the array list are {3, 6, 10, 43, 23}

Answer 1

nums.txt:
5, 3, 6, 10, 43, 23

main.cpp:

#include <iostream>
#include <fstream>

using namespace std;

int main() {
        string fileName;

        cout << "Enter fileName: ";
        cin >> fileName;

        ifstream f(fileName.c_str());
        if(f.fail()) {
                cout << "Unable to find the file" << endl;
                return 1;
        }

        int size;
        f >> size;

        int *data = new int[size];

        for(int i=0; i<size; i++) {
                if(f.peek() == ',') {
                        f.ignore(10, ',');
                }
                if(f.peek() == ' ') {
                        f.ignore(10, ' ');
                }
                f >> data[i];
        }

        cout << "Read data from file." << endl;

        // print result
        for(int i=0; i<size; i++) {
                cout << data[i] << " ";
        }
        cout << endl;

        delete [] data;
}

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