Files

#include <cstdio>
#include <iostream>
#include <string>

void write_to_file(const char* filename,
    const char* str) {
    FILE* pfile = nullptr;
    fopen_s(&pfile, filename, "a");
    if (pfile != nullptr) {
        fprintf(pfile,"%\n", str);
        fclose(pfile);
        printf("%s\n", "Job done.");
    }
    else {
        printf("%s\n","Can not open the file.");
    }
}

void write_to_binfile(
    const char* filename,
    const int* arr,
    const int size
) {
    FILE* pfile = nullptr;
    fopen_s(&pfile, filename, "w");
    if (pfile != nullptr) {
        fwrite(arr, sizeof(arr[0]), size, pfile);
        //fprintf(pfile, "%\n", str);
        fclose(pfile);
        printf("%s\n", "Job done.");
    }
    else {
        printf("%s\n", "Can not open the file.");
    }
}


int main() {


    int arr[]{ 1,2,3,4,5 };
    write_to_binfile("text.dat", arr, 5);
    return 0;
}