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==#if==

<p>To define more generalized conditions.</p>
<p>Multiple conditions are connected by relational operators such as AND(&&), OR(||).</p>

   
<source lang="cpp">#define USA 1
// #define EUP 1
#include <stdio.h>
#if ((1>0) && defined USA)
       #define currency_rate 46
#endif
#if (defined (EUP))
   #define currency_rate 100
#endif
main()
{
    int rs;
    rs = 10 * currency_rate;
    printf ("%d\n", rs);
}</source>
<pre class=codeResult>460</pre>