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copied!<p>The <a href="http://pubs.opengroup.org/onlinepubs/9699919799/functions/scanf.html" rel="nofollow noreferrer"><code>scanf()</code></a> function removes whitespace automatically before trying to parse conversions other than characters. The character formats (primarily <code>%c</code>; also scan sets <code>%[…]</code> — and <code>%n</code>) are the exception; they don't remove whitespace.</p> <p>Use <code>" %c"</code> with a leading blank to skip optional white space. Do not use a trailing blank in a <code>scanf()</code> format string.</p> <p>Note that this still doesn't consume any trailing whitespace left in the input stream, not even to the end of a line, so beware of that if also using <a href="http://en.cppreference.com/w/c/io/getchar" rel="nofollow noreferrer"><code>getchar()</code></a> or <a href="http://en.cppreference.com/w/c/io/fgets" rel="nofollow noreferrer"><code>fgets()</code></a> on the same input stream. We're just getting scanf to skip over whitespace <em>before</em> conversions, like it does for <code>%d</code> and other non-character conversions.</p> <hr> <p>Note that non-whitespace "directives" (to use <a href="http://pubs.opengroup.org/onlinepubs/9699919799/functions/scanf.html" rel="nofollow noreferrer">POSIX scanf terminology</a>) other than conversions, like the literal text in <code>scanf("order = %d", &order);</code> doesn't skip whitespace either. The literal <code>order</code> has to match the next character to be read.</p> <p>So you probably want <code>" order = %d"</code> there if you want to skip a newline from the previous line but still require a literal match on a fixed string, <a href="https://stackoverflow.com/questions/49923312/scanf-run-twice-instead-of-one-time-at-assembly-x86-64">like this question</a>.</p>

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