**Problem :** 
Build a program that reads two strings from the keyboard and generates a third string which consists of combining two strings in such a way that the characters of the first string are placed in odd positions while the characters of the second string in even positions. The length of the new string will be twice the length of the smaller string. Display all three strings on the screen.

My solution : (I've code something, but it gives me error. Can anyone show me where is the problem?)

```
   #include <stdio.h>
#include <string.h>

int main()
{
 char str1[100], str2[100], str3[100];
 int i=0;
 int j; 
 int p;  

 printf("Give string  1: \n");
 gets(str1);
 printf("Give string  2: \n");
 gets(str2);

 if(strlen(str1)<strlen(str2)) 
    p=strlen(str1);
 else
   p=strlen(str2);

   j=0;
 for(i=0; i<p*2; i++){
   if(i%2==0)
       str3[i]=str2[j];
     else{
       str3[i]=str1[j];
       j++; }
}

 printf("\n String 3 is :  %d");
 printf("\n String 2 is :  %d");
 printf("\n String 1 is :  %d");
     return 0;
}

```
['https://Stackoverflow.com/questions/61629887', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/-1/']
This can be done in using the popular requests library

```
import requests
url = 'https://www.google.com'
headers=requests.head(url).headers
downloadable = 'attachment' in headers.get('Content-Disposition', '')

```

[Content Disposition Header reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition)
On HTTP protocol level itself, there is no distinction between downloadable and non-downloadable URL. There is an HTTP request and there is a subsequent response. Response body can be a binary file, HTML, image etc..

You can just request the HTTP response header and look for `Content-Type:` and decide whether you want to consider that content-type as downloadable or non-downloadable.