digitalmars.D.learn - BigInt and xor
- Dennis Ritchie (15/15) Mar 24 2015 Tell me, please, how can I replace this code?
- Rene Zwanenburg (5/20) Mar 24 2015 Looks right to me. What output would you expect?
- matovitch (4/19) Mar 24 2015 Hi,
- Ivan Kazmenko (28/43) Mar 24 2015 What exactly is not working?
- Dennis Ritchie (9/35) Mar 24 2015 Everything works. I'm just a little forgotten properties of the
- matovitch (3/10) Mar 24 2015 xor it with -1 instead of 1. (-1 is store as 0xfff..f with the
- Dennis Ritchie (2/4) Mar 24 2015 Thanks.
Tell me, please, how can I replace this code?
import std.conv : to;
import std.bigint : BigInt;
import std.string : format;
import std.stdio : writeln;
void main() {
BigInt[10] bitArr;
ulong n = 18_446_724_073_709_551_614U;
bitArr[0] = format("%b", n).to!BigInt;
writeln(bitArr[0]);
writeln(bitArr[0] ^ 1); // not work
}
Output:
1111111111111111111011011100111101100011000110101011111111111110
1111111111111111111011011100111101100011000110101011111111111111
Mar 24 2015
"Rene Zwanenburg" <renezwanenburg gmail.com>
On Tuesday, 24 March 2015 at 15:45:36 UTC, Dennis Ritchie wrote:
Tell me, please, how can I replace this code?
import std.conv : to;
import std.bigint : BigInt;
import std.string : format;
import std.stdio : writeln;
void main() {
BigInt[10] bitArr;
ulong n = 18_446_724_073_709_551_614U;
bitArr[0] = format("%b", n).to!BigInt;
writeln(bitArr[0]);
writeln(bitArr[0] ^ 1); // not work
}
Output:
1111111111111111111011011100111101100011000110101011111111111110
1111111111111111111011011100111101100011000110101011111111111111
Looks right to me. What output would you expect?
Also, if you need a bit array you can simply use std.container's
Array!bool. It's specialized for bool and uses only one bit per
element.
Mar 24 2015
On Tuesday, 24 March 2015 at 15:45:36 UTC, Dennis Ritchie wrote:
Tell me, please, how can I replace this code?
import std.conv : to;
import std.bigint : BigInt;
import std.string : format;
import std.stdio : writeln;
void main() {
BigInt[10] bitArr;
ulong n = 18_446_724_073_709_551_614U;
bitArr[0] = format("%b", n).to!BigInt;
writeln(bitArr[0]);
writeln(bitArr[0] ^ 1); // not work
}
Output:
1111111111111111111011011100111101100011000110101011111111111110
1111111111111111111011011100111101100011000110101011111111111111
Hi,
Well it works, the las bit is flip isn't it ? What are you trying
to achieve ?
Mar 24 2015
On Tuesday, 24 March 2015 at 15:45:36 UTC, Dennis Ritchie wrote:
Tell me, please, how can I replace this code?
import std.conv : to;
import std.bigint : BigInt;
import std.string : format;
import std.stdio : writeln;
void main() {
BigInt[10] bitArr;
ulong n = 18_446_724_073_709_551_614U;
bitArr[0] = format("%b", n).to!BigInt;
writeln(bitArr[0]);
writeln(bitArr[0] ^ 1); // not work
}
Output:
1111111111111111111011011100111101100011000110101011111111111110
1111111111111111111011011100111101100011000110101011111111111111
What exactly is not working?
The only thing I see lacking is an ability to print a BigInt in
binary via writefln("%b").
Up to 64 bits, arithmetic and bitwise operations, including xor,
are available with long and ulong. Just print the result as
binary:
-----
import std.stdio;
void main() {
ulong n = ulong.max - 0b1000101;
writeln (n);
writefln ("%b", n);
writefln ("%b", n ^ 1);
}
-----
Output:
-----
18446744073709551546
1111111111111111111111111111111111111111111111111111111110111010
1111111111111111111111111111111111111111111111111111111110111011
-----
If you need more than 64 bits, take a look at BitArray here, it
also has xor defined:
In the future, please explain what problem you are trying to
solve, as the wrong code alone often leaves one guessing.
Ivan Kazmenko.
Mar 24 2015
On Tuesday, 24 March 2015 at 16:35:04 UTC, Ivan Kazmenko wrote:What exactly is not working?Everything works. I'm just a little forgotten properties of the operation xor. I just wanted to xor 1 each digit in the number of type BigInt, while I would like to store each number in the binary representation of the array BigInt.The only thing I see lacking is an ability to print a BigInt in binary via writefln("%b").Yes. It would be nice.Up to 64 bits, arithmetic and bitwise operations, including xor, are available with long and ulong. Just print the result as binary: ----- import std.stdio; void main() { ulong n = ulong.max - 0b1000101; writeln (n); writefln ("%b", n); writefln ("%b", n ^ 1); } ----- Output: ----- 18446744073709551546 1111111111111111111111111111111111111111111111111111111110111010 1111111111111111111111111111111111111111111111111111111110111011 -----If you need more than 64 bits, take a look at BitArray here, it also has xor defined:Thanks.In the future, please explain what problem you are trying to solve, as the wrong code alone often leaves one guessing.OK, I will try.
Mar 24 2015
On Tuesday, 24 March 2015 at 17:28:50 UTC, Dennis Ritchie wrote:On Tuesday, 24 March 2015 at 16:35:04 UTC, Ivan Kazmenko wrote:xor it with -1 instead of 1. (-1 is store as 0xfff..f with the classic modular arithmetic)What exactly is not working?Everything works. I'm just a little forgotten properties of the operation xor. I just wanted to xor 1 each digit in the number of type BigInt, while I would like to store each number in the binary representation of the array BigInt.
Mar 24 2015
On Tuesday, 24 March 2015 at 17:35:14 UTC, matovitch wrote:xor it with -1 instead of 1. (-1 is store as 0xfff..f with the classic modular arithmetic)Thanks.
Mar 24 2015