Home » Archimedes archive » Acorn User » AU 1997-10 A.adf » Extras » Apple][e/PD/BOB/ARMBOB/!ArmBob/progs/intsqrt
Apple][e/PD/BOB/ARMBOB/!ArmBob/progs/intsqrt
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Archimedes archive » Acorn User » AU 1997-10 A.adf » Extras |
| Filename: | Apple][e/PD/BOB/ARMBOB/!ArmBob/progs/intsqrt |
| Read OK: | ✔ |
| File size: | 0194 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
sqroot (N)
{
local k2, u, v, u2, n;
if ( 2 > N) return (N);
u = N;
k2 = 0;
while (u >>= 2) k2++;
u = 1 << k2;
v = u;
u2 = u << k2;
while (k2--)
{
v >>= 1;
n = (u + u + v)<<k2;
n += u2;
if (n <= N)
{
u += v;
u2 = n;
}
}
return (u);
}
main()
{
print("Positive integer :");
x = val(input());
print("Integer part of square root is ",
sqroot(x),
"\n");
}
00000000 73 71 72 6f 6f 74 20 28 4e 29 0a 7b 0a 20 6c 6f |sqroot (N).{. lo|
00000010 63 61 6c 20 6b 32 2c 20 75 2c 20 76 2c 20 75 32 |cal k2, u, v, u2|
00000020 2c 20 6e 3b 0a 20 69 66 20 28 20 32 20 3e 20 4e |, n;. if ( 2 > N|
00000030 29 20 72 65 74 75 72 6e 20 28 4e 29 3b 0a 20 75 |) return (N);. u|
00000040 20 3d 20 4e 3b 0a 20 6b 32 20 3d 20 30 3b 0a 20 | = N;. k2 = 0;. |
00000050 77 68 69 6c 65 20 28 75 20 3e 3e 3d 20 32 29 20 |while (u >>= 2) |
00000060 6b 32 2b 2b 3b 0a 20 75 20 3d 20 31 20 3c 3c 20 |k2++;. u = 1 << |
00000070 6b 32 3b 0a 20 76 20 3d 20 75 3b 0a 20 75 32 20 |k2;. v = u;. u2 |
00000080 3d 20 75 20 3c 3c 20 6b 32 3b 0a 20 77 68 69 6c |= u << k2;. whil|
00000090 65 20 28 6b 32 2d 2d 29 0a 20 7b 0a 20 20 76 20 |e (k2--). {. v |
000000a0 3e 3e 3d 20 31 3b 0a 20 20 6e 20 3d 20 28 75 20 |>>= 1;. n = (u |
000000b0 2b 20 75 20 2b 20 76 29 3c 3c 6b 32 3b 0a 20 20 |+ u + v)<<k2;. |
000000c0 6e 20 2b 3d 20 75 32 3b 0a 20 20 69 66 20 28 6e |n += u2;. if (n|
000000d0 20 3c 3d 20 4e 29 0a 20 20 7b 0a 20 20 20 75 20 | <= N). {. u |
000000e0 2b 3d 20 76 3b 0a 20 20 20 75 32 20 3d 20 6e 3b |+= v;. u2 = n;|
000000f0 0a 20 20 7d 0a 20 7d 0a 20 72 65 74 75 72 6e 20 |. }. }. return |
00000100 28 75 29 3b 0a 7d 0a 0a 6d 61 69 6e 28 29 0a 7b |(u);.}..main().{|
00000110 0a 20 70 72 69 6e 74 28 22 50 6f 73 69 74 69 76 |. print("Positiv|
00000120 65 20 69 6e 74 65 67 65 72 20 3a 22 29 3b 0a 20 |e integer :");. |
00000130 78 20 3d 20 76 61 6c 28 69 6e 70 75 74 28 29 29 |x = val(input())|
00000140 3b 0a 20 70 72 69 6e 74 28 22 49 6e 74 65 67 65 |;. print("Intege|
00000150 72 20 70 61 72 74 20 6f 66 20 73 71 75 61 72 65 |r part of square|
00000160 20 72 6f 6f 74 20 69 73 20 22 2c 0a 20 20 20 20 | root is ",. |
00000170 20 20 20 20 20 73 71 72 6f 6f 74 28 78 29 2c 0a | sqroot(x),.|
00000180 20 20 20 20 20 20 20 20 20 22 5c 6e 22 29 3b 0a | "\n");.|
00000190 7d 0a 20 20 |}. |
00000194 
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