Timezone calculator.

[Moneo]

Boy, do we have a can of worms regarding timezones.

I consulted my Encyclopaedia Britannica and World Book Encyclopedia and they both define 24 standard timezones.

There are numerous exceptions, but for this challenge, we will use the 24 timezones on the following list. I have included principal country/city names.

Also for this challenge, we will ignore the issue of daylight savings or summer time. It becomes almost impossible for our program to determine if the subject timezome uses daylight savings, when it starts and ends, and whether it advances one hour or two. Therefore, we will leave this daylight time adjustment up to the user of the program.

TIMEZONES:
GMT = London
GMT - 1 = Reykjavik
GMT - 2 = Greenland
GMT - 3 = Rio de Janeiro, Brazil
GMT - 4 = Santiago de Chile
GMT - 5 = New York
GMT - 6 = Chicago
GMT - 7 = Denver
GMT - 8 = Seattle
GMT - 9 = Alaska
GMT -10 = Honolulu
GMT -11 = Midway Island
GMT -12 (does not exist, see GMT +12)

continuing in a circle around the world............
GMT +12 = New Zealand
GMT +11 = Solomon Islands
GMT +10 = Sydney
GMT + 9 = Tokyo
GMT + 8 = Hong Kong, and China
GMT + 7 = Bangkok
GMT + 6 = Omsk, Russia
GMT + 5 = Karachi
GMT + 4 = Stalingrad
GMT + 3 = Moscow
GMT + 2 = Cairo
GMT + 1 = Berlin

Comments?
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