<title>Got Ya</title> <head> <script language="JavaScript"> </script> </head> <body bgcolor="#ffffcc"> <hr> <center> <h1>Got Ya</h1> </center> <hr> <ul> <li><a href="#num1">== and =</a> <li><a href="#num1">if</a> </ul> <a name=num1> <hr> An error which almost every C programmer has made is shown below: <pre> main() { int left=10; if ( left = 5 ) { puts(" Values are equal..."); } } </pre> The program assigns 5 to the variable <b>left</b> and returns 5. This is interpreted as <a href="../CONCEPT/true_false.html">TRUE</a> and causes the <a href="../FUNCTIONS/puts.html">puts</a> statement to be executed everytime. <p> Here is the corrected program. <pre> main() { int left=10; if ( left == 5 ) /* Double equals required. */ { puts(" Values are equal..."); } } </pre> <hr> <hr> <h2>See Also:</h2> <img src="../../GRAPHICS/whiteball.gif"> <a href="idioms.html">Coding idioms</a>.<p> <p> <hr> <p> <center> <table border=2 width="80%" bgcolor="ivory"> <tr align=center> <td width="25%"> <a href="../cref.html"> Top</a> </td><td width="25%"> <a href="../master_index.html"> Master Index</a> </td><td width="25%"> <a href="keywords.html"> Keywords</a> </td><td width="25%"> <a href="../FUNCTIONS/funcref.htm"> Functions</a> </td> </tr> </table> </center> <p> <hr> <address>Martin Leslie </address><p> </body> </html>