printf not outing thing read from scanf

Question

scanf can read optimally signed decimal,octal, or hexadecimal input but printf can't output said read input? Or is there some other specifier I'm not aware of and not using.

example code

scanf("%i", &x);     //enter 0150 (octal)                     
printf("%i ",x);     //outputs 104(decimal)

Read the man page for `printf`. It has a list of all of the conversion specifiers. — user3386109, Feb 24 '16 at 04:16
those specifiers are specific, but I was wondering if there was one specifier that encompassed 3 specifiers — j.yang29, Feb 24 '16 at 04:21
%i can read optimally signed decimal,octal, or hexadecimal and the argument is pointed to an int. — j.yang29, Feb 24 '16 at 04:22
@vvid No, because C is not an object-oriented language, so variable `x` contains no information except a value. You need to choose the format that you want to use to display that value. — user3386109, Feb 24 '16 at 04:27
@chux, damn, I stand corrected. I had my `printf` and `scanf` swapped. — David C. Rankin, Feb 24 '16 at 04:29
Let us pretend there was such a specifier, called `Z`. What would you expect `printf("%Z ",x);` to print? `x` has no "memory" of how its value originated. — chux - Reinstate Monica, Feb 24 '16 at 04:32
@chux it could be made to work if `%z` consumed 2 arguments, one for the base and another for the value. Kind of like `%*s` consumes 2 arguments. — Tom Karzes, Feb 24 '16 at 05:01
@Tom Karzes You mean like [TO_BASE(x, 2), TO_BASE(x, 36)](http://stackoverflow.com/a/34292061/2410359)? — chux - Reinstate Monica, Feb 24 '16 at 05:11
@chux Yeah pretty much, but without the need to provide storage for the result. — Tom Karzes, Feb 24 '16 at 05:12
@Tom Karzes Note, no storage variables were explicitly declared. IAC, I was hoping to find OP's point-of-view — chux - Reinstate Monica, Feb 24 '16 at 05:13

score 2 · Answer 1 · answered Feb 24 '16 at 05:47

2

Yes, there is another specifier. You should read as string and write what you read to write exactly what you read.

char x[100];
scanf("%99s", x);
printf("%s ", x);

answered Feb 24 '16 at 05:47

MikeCAT

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Nice answer, but there might be some problem with the data type which not actually a numeric. Since it's in array of char, some might found it difficult to operate/manipulate the array of char with other numeric data. Still, it's nice answer. – ichan-akira Feb 24 '16 at 09:32

score 0 · Answer 2 · edited May 23 '17 at 12:15

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See here, printf doesn't identify "%i" and "%d" separately. But it is identified in scanf. Also please write the question properly next time :)

These links may help you-

edited May 23 '17 at 12:15

Community

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answered Feb 24 '16 at 04:24

Tarang Gupta

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score 0 · Accepted Answer · answered Feb 24 '16 at 04:28

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Guess there is no specifier that does what %i can do in scanf, I wasn't sure if there was one or not but ichan confirmed that there isn't one

answered Feb 24 '16 at 04:28

j.yang29

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ichan-akira · Answer 4 · 2016-02-24T09:11:40.387

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You might found this reference is useful to you:

printf
http://www.cplusplus.com/reference/cstdio/printf/

scanf
http://www.cplusplus.com/reference/cstdio/scanf/

EDIT:
There is no single specifier, that one size fit all. You should know what you will be printing, and use the specific specifier to get the job done.

edited Feb 24 '16 at 09:11

answered Feb 24 '16 at 04:21

ichan-akira

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The input is not known and is determined by the user. But I see, if there is no one size fits all then I am out of luck – j.yang29 Feb 24 '16 at 04:27
While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - [From Review](/review/low-quality-posts/11383535) – Magisch Feb 24 '16 at 09:02
@Magisch I've been added the answer from the link. I'm using image, since Stack Overflow doesn't support html tag.
– ichan-akira Feb 24 '16 at 09:31

printf not outing thing read from scanf

4 Answers4