document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204708>Question 1204708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In the USA, ZIP codes are used as an alternative to the postcode system<BR>\n" );
document.write( "used in the UK. A ZIP code is a five-digit number which may start with a<BR>\n" );
document.write( "zero  -  so there are, in total, 100 000 possible ZIP codes, from 00000 to<BR>\n" );
document.write( "99999.<BR>\n" );
document.write( "Some ZIP codes are ambiguous, meaning that, when shown on a digital<BR>\n" );
document.write( "display, they would show a different code if read the wrong way up.<BR>\n" );
document.write( "For example, 10118 (which happens to be the ZIP code for the Empire<BR>\n" );
document.write( "State building in New York), if read upside-down, would be 81101 (the<BR>\n" );
document.write( "ZIP code for Alamosa, a town in Colorado), so both 10118 and 81101 are<BR>\n" );
document.write( "ambiguous ZIP codes.<BR>\n" );
document.write( "Given that the figures used on a digital display are the ones shown<BR>\n" );
document.write( "below (0 1 2 3 4 5 6 7 8 9), determine the total number of non-ambiguous ZIP codes. </SPAN>\n" );
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document.write( "Here's the list of possible digits when using a digital display (think of an alarm clock)<BR>\n" );
document.write( "Another term for it is called <a  rel=nofollow HREF=\"https://en.wikipedia.org/wiki/Seven-segment_display\">seven-segment display</a> because we need at most 7 lines to form the digits 0 through 9<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" src = \"https://i.stack.imgur.com/kfYal.png\"><BR>\n" );
document.write( "Image Source<BR>\n" );
document.write( "<a  rel=nofollow HREF=\"https://codegolf.stackexchange.com/questions/151125/mirrored-digital-clock\">https://codegolf.stackexchange.com/questions/151125/mirrored-digital-clock</a>\r<BR>\n" );
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document.write( "0,1, and 8 can be rotated 180 degrees about the center and the digits won't change (as mentioned in the instructions).<BR>\n" );
document.write( "If we rotated 6, then it turns into 9, and vice versa.\r<BR>\n" );
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document.write( "Rotating a 2 will have it land on itself. Meaning it won't change. Same goes for 5.\r<BR>\n" );
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document.write( "Here are all of the ambiguous digits<BR>\n" );
document.write( "0, 1, 2, 5, 6, 8, 9\r<BR>\n" );
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document.write( "Here are the non-ambiguous digits<BR>\n" );
document.write( "3, 4, 7\r<BR>\n" );
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document.write( "There are 3 items in that non-ambiguous set of digits.<BR>\n" );
document.write( "Having 5 such digits, where repeats are allowed, would give us 3^5 = <font color=red>243</font> non-ambiguous zip codes.<BR>\n" );
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