Invalid nginx directive

[sharulhafiz]

I tried to paste this directive in web server settings

        ##DM - uncomment following line for domain mapping   
        #listen 80 default_server;
    #server_name example.com *.example.com ;
    ##DM - uncomment following line for domain mapping
    #server_name_in_redirect off;

    #access_log   /var/log/nginx/example.com.access.log;
    #error_log    /var/log/nginx/example.com.error.log;

    #root /var/www/example.com/htdocs;
    index index.php;

    if (!-e $request_filename) {
        rewrite /wp-admin$ $scheme://$host$uri/ permanent; 
        rewrite ^(/[^/]+)?(/wp-.*) $2 last;
        rewrite ^(/[^/]+)?(/.*\.php) $2 last;
    }

    set $cache_uri $request_uri;

    # POST requests and urls with a query string should always go to PHP
    if ($request_method = POST) {
        set $cache_uri 'NULL';
    }  
    if ($query_string != "") {
        set $cache_uri 'NULL';
    }  

    # Don't cache uris containing the following segments
    if ($request_uri ~* "(/wp-admin/|/xmlrpc.php|/wp-(app|cron|login|register|mail).php|wp-.*.php|/feed/|index.php|wp-comments-popup.php|wp-links-opml.php|wp-locations.php|sitemap(_index)?.xml|[a-z0-9_-]+-sitemap([0-9]+)?.xml)") {
        set $cache_uri 'NULL';
    }  

    # Don't use the cache for logged in users or recent commenters
    if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_logged_in") {
        set $cache_uri 'NULL';
    }

    # Use cached or actual file if they exists, otherwise pass request to WordPress
    location / {
        try_files /wp-content/cache/supercache/$http_host/$cache_uri/index.html $uri $uri/ /index.php?$args ;
    }   

    location ~ \.php$ {
        try_files $uri =404;
        include fastcgi_params;
        fastcgi_pass 127.0.0.1:9000;
    }

    location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ {
        access_log off;    log_not_found off; expires max;
    }

    location = /robots.txt { access_log off; log_not_found off; }
    location ~ /\. { deny  all; access_log off; log_not_found off; }

However, I got this error on saving

Invalid nginx configuration: nginx: [emerg] duplicate location "/" in /opt/www/vhost/system/corporateaffairs.utm.my/conf/vhost_nginx.conf:40 nginx: configuration file /etc/nginx/nginx.conf test failed

What is the correct way to replace nginx.conf?

I got the directive here https://rtcamp.com/wordpress-nginx/tutorials/multisite/subdirectories/wp-super-cache/