You know you’re a nerd when you look at today’s date, November 1st, as 11-01 and then you think, “That’s a binary number!” Yeah, nerd.
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\nWhen thinking of a topic for today’s Lesson, I kept fixating on the date. It got me thinking about how many other dates through the year — month\/date combinations — are binary in nature, using only the digits one and zero?<\/p>\n
If this were a trivia question during a pub quiz, I’d riffle though my brain to come up with a quick answer. (And if you’re a nerd, you’ve probably already done so.) But instead, and seeing how this post is supposed to be about C programming, I thought I’d write code that would find all the annual binary dates and output the entire list.<\/p>\n
This first part of this code is presented below. It’s a program that churns through the months and days of the year, outputting each as a two-digit value. After all, if you’re going to hunt for those binary dates, you must generate the full field in which to search. Consider this code an initial step.<\/p>\n
\r\n#include <stdio.h>\r\n\r\nint main()\r\n{\r\n int month,d;\r\n int days[12] = {\r\n 31, 28, 31, 30, 31, 30,\r\n 31, 31, 30, 31, 30, 31\r\n };\r\n\r\n for( month=0; month<12; month++ )\r\n {\r\n for( d=0; d<days[month]; d++ )\r\n printf(\"%02d%02d\\n\",\r\n month+1,\r\n d+1\r\n );\r\n }\r\n\r\n return 0;\r\n}<\/pre>\nInteger variable month<\/code> tracks months of the year; int<\/em> variable d<\/code> tracks the days of a month.<\/p>\nArray days[]<\/code> holds the number of days in each month. Because February 29th isn’t a binary value, I just omitted it as well as any silly leap year calculations.<\/p>\nNested for<\/em> loops work through the month and day values. The printf()<\/em> statement outputs the month\/day date as four-digit value. The %02d<\/code> placeholder ensures that output is in the format of a decimal integer, two-digits wide, with a leading zero for single-digit values. The value 1 is added to variables month<\/code> and d<\/code> in the printf()<\/em> statement to make the output human-readable.<\/p>\nHere’s the output:<\/p>\n
0101
\n0102
\n0103
\n0104
\n0105
\n0106
\n.
\n.
\n.
\n1227
\n1228
\n1229
\n1230
\n1231<\/code><\/p>\nThat’s 365 lines of output, each expressing a day of the years as a date two digits wide.<\/p>\n
The next phase of the project is to set this output into a form that can be tested for binary values. I continue this task in next week’s Lesson<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Check it out: November 1st is 11-01, which is 13 decimal or 0xD in hex. I’m a nerd! Continue reading