Created
December 4, 2010 19:56
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Integer Cube Root (64-bit safe version)
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| ulong icbrt64(ulong x) { | |
| int s; | |
| ulong y, b, bs; | |
| s = 30; | |
| y = 0; | |
| while (s >= 0) { | |
| y += y; | |
| b = 3*y*(y * 1) + 1; | |
| bs = b << s; | |
| s -= 3; | |
| if (x >= bs && b == (bs >> s)) { | |
| x -= bs; | |
| y++; | |
| } | |
| } | |
| return y; | |
| } |
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should be b = 3_y_(y +1) + 1;
and s -= 3; should be after b == (bs >> s)