I agree with the above posters. We need to know precisely what Operating System you have and exactly what Shell you have. Nowadays it is quite rare to encounter a raw Bourne Shell.
The palindrone question is an advanced text manipulation exercise which usually requires you to first determine the length of the string, then reverse the order of the characters in the string, and then compare the before and after string. If they are the same then it is a palindrome.
There are some extraordinarily complex methods for doing this involving arrays however it may be worth checking out the unix "rev" command if this command is allowed by your tutor.
This example script should work with any true Bourne Shell.
Ps. The straightforward answer to the original question is "zero". I do hope that this isn't an interview question.
However if you continue from 100001 and attempt to find the next palindrone (which I guess is 101101) by incremental methods then this is much more interesting.
Conforming to old Bourne Shell syntax we arrive at something like this:
If your course context suggests that the string reversal bit should be done with string arrays, then it is up to you to how you reverse the string.
Last edited by methyl; 07-30-2011 at 09:24 PM..
Reason: Wrong guess.
Hi,
Program A: uses pipe()
I am able to read the stdout of PROGAM B (stdout got through system() command) into PROGRAM A using:
* child
-> dup2(fd, STDOUT_FILENO);
-> execl("/path/PROGRAM B", "PROGRAM B", NULL);
* parent
-> char line;
-> read(fd, line, 100);
Question:
---------... (1 Reply)
Hi,
Program A: uses pipe()
I am able to read the stdout of PROGAM B (stdout got through system() command) into PROGRAM A using:
* child
-> dup2(fd, STDOUT_FILENO);
-> execl("/path/PROGRAM B", "PROGRAM B", NULL);
* parent
-> char line;
-> read(fd, line, 100);
Question:
---------... (3 Replies)
Hi,
I wanted to know if i can write a program using switches and signals, etc to trace execution of other unix program which calls c program internally.
If yes how? If not with signals and switches then are there any other methods apart from debugging with gdb/dbx. (3 Replies)
Can anyone tell me how to.....
program to create multiple threads (one master thread and rest worker threads) and using the threads write into and read from shared memory
Restrictions:
Only one thread should be able to read at any instant of time into shared memory region.
Only one... (2 Replies)
Hi,
i want to write a script that executes a program (exec?) .
this program then requires a filename as input.
how do i give it this input in the script so the program will be complete run and close by the script.
e.g.
exec prog.exe
program then asks for filename
"enter filename:"... (1 Reply)
I wrote a simple program that generates a random word 10,000,000 times.
I wrote it in python, then in C++ and compared the two completion times. The python script was faster! Is that normal? Why would the python script be faster? I was under the impression that C++ was faster. What are some of... (2 Replies)
Hi All,
Probably this is a repeated question. My knowledge in this is limited and i got confused on all those materials i got in google search.
We use #include <> to include a predefined library like stdio.h
i saw somewhere that #include "" includes a man made module(another C program). IS... (2 Replies)
Long story short: I'm working inside of a Unix SSH under a bash shell. I have to code a C program that generates a random number. Then I have to call the compiled C program with a Perl program to run the C program 20 times and put all the generated random #s into a text file, then print that text... (1 Reply)
I created a program, so a kid can practice there math on it. It dispenses varies math problems and the kid must input an answer. I also want it to grade the work they have done, but I can't find the best place for it to print out the grade.
I have:
if ( $response =~ m/^/ ) {
$user_wants_to_quit... (1 Reply)
Discussion started by: germany1517
1 Replies
LEARN ABOUT PHP
intval
INTVAL(3) 1 INTVAL(3)intval - Get the integer value of a variableSYNOPSIS
int intval (mixed $var, [int $base = 10])
DESCRIPTION
Returns the integer value of $var, using the specified $base for the conversion (the default is base 10). intval(3) should not be used on
objects, as doing so will emit an E_NOTICE level error and return 1.
PARAMETERS
o $var
- The scalar value being converted to an integer
o $base
- The base for the conversion
Note
If $base is 0, the base used is determined by the format of $var:
o if string includes a "0x" (or "0X") prefix, the base is taken as 16 (hex); otherwise,
o if string starts with "0", the base is taken as 8 (octal); otherwise,
o the base is taken as 10 (decimal).
RETURN VALUES
The integer value of $var on success, or 0 on failure. Empty arrays return 0, non-empty arrays return 1.
The maximum value depends on the system. 32 bit systems have a maximum signed integer range of -2147483648 to 2147483647. So for example
on such a system, intval('1000000000000') will return 2147483647. The maximum signed integer value for 64 bit systems is
9223372036854775807.
Strings will most likely return 0 although this depends on the leftmost characters of the string. The common rules of integer casting
apply.
EXAMPLES
Example #1
intval(3) examples
The following examples are based on a 32 bit system.
<?php
echo intval(42); // 42
echo intval(4.2); // 4
echo intval('42'); // 42
echo intval('+42'); // 42
echo intval('-42'); // -42
echo intval(042); // 34
echo intval('042'); // 42
echo intval(1e10); // 1410065408
echo intval('1e10'); // 1
echo intval(0x1A); // 26
echo intval(42000000); // 42000000
echo intval(420000000000000000000); // 0
echo intval('420000000000000000000'); // 2147483647
echo intval(42, 8); // 42
echo intval('42', 8); // 34
echo intval(array()); // 0
echo intval(array('foo', 'bar')); // 1
?>
NOTES
Note
The $base parameter has no effect unless the $var parameter is a string.
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 5.1.0 | |
| | |
| | Throws E_NOTICE and returns 1, when an object is |
| | passed to $var. |
| | |
+--------+---------------------------------------------------+
SEE ALSO boolval(3), floatval(3), strval(3), settype(3), is_numeric(3), Type juggling, BCMath Arbitrary Precision Mathematics Functions.
PHP Documentation Group INTVAL(3)