input - Read two characters consecutively using scanf() in C -

-

i trying input 2 characters user t number of times. here code : 

int main() {     int t;     scanf("%d",&t);     char a,b;      for(i=0; i<t; i++)     {         printf("enter a: ");         scanf("%c",&a);          printf("enter b:");         scanf("%c",&b);     }     return 0; }

strangely output first time is:

enter a:  enter b:

that is, code doesn't wait value of a.

the problem scanf("%d", &t) leaves newline in input buffer, consumed scanf("%c", &a) (and hence a assigned newline character). have consume newline getchar();.

another approach add space in scanf() format specifier ignore leading whitespace characters (this includes newline). example:

for(i=0; i<t; i++) {     printf("enter a: ");     scanf(" %c",&a);      printf("enter b: ");     scanf(" %c",&b); }

if prefer using getchar() consume newlines, you'd have this:

for(i=0; i<t; i++) {     getchar();     printf("enter a: ");     scanf("%c",&a);      getchar();     printf("enter b:");     scanf("%c",&b);  }

i consider former approach superior, because ignores arbitrary number of whitespaces, whereas getchar() consumes one.


Comments

Post a Comment

Popular posts from this blog

C# random value from dictionary and tuple -

-
i have following code, , need random item contains string "region_1" dictionary. public static dictionary<int, tuple<string, int, currencytype>> itemarray = new dictionary<int, tuple<string, int, currencytype>>() { { 0xb3e, new tuple<string, int, currencytype>("region_1", 1500, currencytype.fame) } }; public static int generateitemid(string shopid) { var generateditem = itemarray.elementat(new random().next(0, itemarray.count)).key; } how select this? it's not possible efficiently... first create static random @ class level... prevent non-random behaviour if run query on short period of time... (it's seeded discrete clock) static random rnd = new random(); then: var item = itemarray.values .where(t => t.item1 == shopid) .orderby(_ => rnd.next()) .firstordefault()
Read more

.htaccess - htaccess convert request to clean url and add slash at the end of the url -

-
ok , searched more 4 days , more 20 posts here in stach or in websites without kind of success first here htaccess file rewriteengine on rewriterule ^([a-za-z0-9_]+)/?$ index.php?page=$1 [nc] rewriterule ^([a-za-z0-9_]+)\/([a-za-z0-9_]+)\/?$ index.php?page=$1&action=$2 [nc] i tried many codes 1 worked me can call request , works me www.example.com/pagename => www.example.com/index.php?page=pagename here questions , please provide me information "in detail" understand code well 1- how convert request automatically www.example.com/index.php?page=pagename www.example.com/pagename 2- if tried add slash @ end shows me page without images or styling mean www.example.com/pagename => works www.example.com/pagename/ => doesn't work that's :) for first part need 301 rule this: rewritecond %{the_request} /index\.php\?page=([^\s&]+) [nc] rewriterule ^ /%1? [r=301,l] for second part use absolute path in css, js, images files r...
Read more

cgi - How do I interpret URLs without extension as files rather than missing directories in nginx? -

-
so i'm trying install zoneminder , have run under nginx, has few compiled files need run using fast-cgi. these files lack extension. if file has extension, there no issue , nginx interprets file , return 404 if can't find it. if has no extension, assume it's directory , return 404 when can't find sort of index page. here have now: # security camera domain. server { listen 888; server_name mydomain.com; root /srv/http/zm; # enable php support. include php.conf; location / { index index.html index.htm index.php; } # enable cgi support. location ~ ^/cgi-bin/(.+)$ { alias /srv/cgi-bin/zm/; fastcgi_pass unix:/run/fcgiwrap.sock; fastcgi_param script_filename $document_root/$1; include fastcgi.conf; } } the idea is, under cgi-bin directory goes through fastcgi pipe. any idea on howi can fix this? upon closer inspection, realized zoneminder has 2 cgi sc...
Read more