Read list of numbers in txt file and store to array C

Consider the following modification to your code:

#include <stdio.h>

int main(void) {
    int tek;
    int radica[50];

    // open file
    FILE *myFile = fopen("numbers.txt", "r");
    // if opening file fails, print error message and exit 1
    if (myFile == NULL) {
        perror("Error: Failed to open file.");
        return 1;
    }

    // read values from file until EOF is returned by fscanf
    for (int i = 0; i < 50; ++i) {
        // assign the read value to variable (tek), and enter it in array (radica)
        if (fscanf(myFile, "%d", &tek) == 1) {
            radica[i] = tek;
        } else {
            // if EOF is returned by fscanf, or in case of error, break loop
            break; 
        }
    }

    // close file
    fclose(myFile);
    return 0;
}

Any number read by fscanf will be assigned to tek, and entered in the array radica, until fscanf returns EOF, at which point the loop breaks. As already mentioned, to determine when end of file is reached, it is not the variable tek that is compared to EOF but rather the return of fscanf.