Why 12/13 value is 1 in c#

Question

I tried this expression 12/13 in c# and I got value as 1 When I cast the value to double then actual value is coming.

Can someone explain me why this is happening?

Thanks Ajit

*Integer division*: when *both* arguments are integers, the result must be integer as well: `12 / 13 == 0` — Dmitry Bychenko, May 24 '18 at 11:13
This is mentioned about 1000 times on the internet, to be a programmer you will need to research things like this — TheGeneral, May 24 '18 at 11:13
@Ajit how did you get 1? In *mathematics* integer division always returns 0, not 1 if the dividend is less than the divisor. In C# `12/13` returns 0. How did you get that 1? — Panagiotis Kanavos, May 24 '18 at 11:18
To be fair, the term Integer Division was hard to find for me aswell. I never heard of it before. Maybe its different for someone who's motherlanguage it is. — BotMaster3000, May 24 '18 at 11:18
@BotMaster3000 elementary school? That's just plain old division — Panagiotis Kanavos, May 24 '18 at 11:19
@PanagiotisKanavos Yeah I just mean the english word for it. I didnt know the english equivalent for it til then. — BotMaster3000, May 24 '18 at 11:20
Like operands return result of the same type. Explicit conversion is required. — c0degeas, May 24 '18 at 11:24
To explain the downvote flood: no research(many duplicates), no code, not reproducible(result is 0 instead of 1), off-topic on SO ("explain behaviour" belongs to tutorials or documentation) — Tim Schmelter, May 24 '18 at 11:29

score 3 · Accepted Answer · answered May 24 '18 at 11:15

3

It is because of Integer Division. Because both of your values are Integers, the result will be an integer as well.

You could do a *1.0 to force a double whenever you do a calculation, and it also doesnt change the solution.

answered May 24 '18 at 11:15

BotMaster3000

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Instead of `* 1.0`, a more *readable* choice is to use either suffix `12d` or fractional part `12.0` – Dmitry Bychenko May 24 '18 at 11:19
@DmitryBychenko yes of course, but if you are working with integer-variables, it will be hard to do so. For hardcoded numbers your approach of course is more readable – BotMaster3000 May 24 '18 at 11:39

Codor · Answer 2 · 2018-05-24T11:17:01.020

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The value of 12/13 is smaller than 1, which means that due to integer trunctaion it will truncated to 0.

edited May 24 '18 at 11:17

answered May 24 '18 at 11:13

Codor

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"rounded" is not the correct word to use here. If use this word then it means 3.6 will rounded to 4 which is false. – CodeNotFound May 24 '18 at 11:16
I changed the answer as indeed the explanation might have been misleading. However, according to [this](https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero) Wikipedia article, _rounding_ can refer to various operations which replace one value by possibly another one. – Codor May 24 '18 at 11:19
Indeed but the correct expression (based on the link who use on your comment) wiil be _rounding down_. – CodeNotFound May 24 '18 at 11:21

score 0 · Answer 3 · answered May 24 '18 at 11:18

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Any operation with integer results answer in integer. any operation with double results answer in double. That is default to change scenario you need to cast so that you can get result per your need.

answered May 24 '18 at 11:18

Ujwal Neupane

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Could you please teach me how to post answer [after](https://stackoverflow.com/posts/50507884/timeline) question is closed? Or is it [not closed](https://meta.stackexchange.com/q/283325/299295)? Hmm... – Sinatr May 24 '18 at 11:38
You're a wizard Ujwal. – Daxtron2 May 24 '18 at 12:12
LOL I never knew that i had such power :D may be some bug. – Ujwal Neupane May 24 '18 at 18:24

Why 12/13 value is 1 in c#

3 Answers3