Leap year calculation

year=2010; math=`echo "$year%4" | bc`; [ ! -z $year ] && [ $math -eq 0 ] && echo "$year is leap year!" || echo "$year isn't leap year";

By: mvrilo
2010-03-30 15:33:00

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What Others Think

This doesn't work for all leap years. If a year is evenly divisible by 4 and 100, but not 400, then it's not a leap year. For example, 2200 is divisible by 4, but it's not a leap year. Here's a bash function that takes a year as an argument and returns whether or not it's a leap year. leapyear(){ [ $[$1%400] -eq 0 ]&&{ echo $1' is a leap year!';return;};[ $[$1%100] -eq 0 ]&&{ echo $1' is not a leap year.';return;};[ $[$1%4] -eq 0 ]&&echo $1' is a leap year!'||echo $1' is not a leap year.';}
eightmillion · 633 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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