Extract Username from Post Request

Task

Implement the function get_username.

• Write a function that extracts the username from a post request path
• The path format is /post?user=<username>&message=<message>
• Return an interior pointer to the username within the original string
• You should modify the string by replacing the & after the username with \0

Function Signature

// Given a /post request path, return a pointer to the username
char* get_username(char* post_request);

Note

• Find user= in the string
• The username starts immediately after user=
• The username ends at the & character
• Replace the & with \0 to terminate the username string
• Return a pointer to the start of the username (an interior pointer into the original string)
• You may assume the input always has the format /post?user=<username>&message=<message>

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Example

Input	Output
/post?user=joe&message=hi	joe
/post?user=aaron&message=sup	aaron
/post?user=alice&message=hello%20world	alice
/post?user=bob&message=test	bob
/post?user=x&message=short	x

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Code

#include <string.h>
#include <stdio.h>
 
char *get_username(char *post_request)
{
    char* user = strstr(post_request, "user=") + 5;
    char* end = strstr(user, "&");
    *end = 0;
    return user;
}