document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1135387>Question 1135387</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Six coins are lying in a triangle. You have to move<BR>\n" );
document.write( "some coins to place them in a circle as you can see in the<BR>\n" );
document.write( "second picture. How many coins must be moved at<BR>\n" );
document.write( "least?  </SPAN>\n" );
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document.write( "Moving 2 coins can make a circle; moving only 1 can't.<br><BR>\n" );
document.write( "Think of the 6 coins when they are in a circle as the vertices of a regular hexagon.<br><BR>\n" );
document.write( "The problem then becomes determining the minimum number of coins that have to be moved from the original triangular array to accomplish that.<br><BR>\n" );
document.write( "Then the problem is to find the largest number of the 6 coins in the original array that do NOT need to be moved to become vertices of a regular hexagon.<br><BR>\n" );
document.write( "A look at the original array shows that 4 of the 6 coins can stay where they are.  For example....<br><PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
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document.write( "        1                    6   1\r\n" );
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document.write( "      2   3        -->     2        3\r\n" );
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document.write( "    4   5   6                4   5<br></PRE> </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );