CUBES - Perfect Cubes

For hundreds of years Fermat's Last Theorem, which stated simply that for n > 2 there exist no integers a, b, c > 1 such that an = bn + cn, has remained elusively unproven. (A recent proof is believed to be correct, though it is still undergoing scrutiny.) It is possible, however, to find integers greater than 1 that satisfy the "perfect cube" equation a3 = b3 + c3 + d3 (e.g. a quick calculation will show that the equation 123 = 63 + 83 + 103 is indeed true). This problem requires that you write a program to find all sets of numbers {a, b, c, d} which satisfy this equation for a ≤ 100.

The output should be listed as shown below, one perfect cube per line, in non-decreasing order of a (i.e. the lines should be sorted by their a values). The values of b, c, and d should also be listed in non-decreasing order on the line itself. There do exist several values of a which can be produced from multiple distinct sets of b, c, and d triples. In these cases, the triples with the smaller b values should be listed first.

Note that the programmer will need to be concerned with an efficient implementation. The official time limit for this problem is 2 minutes, and it is indeed possible to write a solution to this problem which executes in under 2 minutes on a 33 MHz 80386 machine. Due to the distributed nature of the contest in this region, judges have been instructed to make the official time limit at their site the greater of 2 minutes or twice the time taken by the judge's solution on the machine being used to judge this problem.

The first part of the output is shown here:

Cube = 6, Triple = (3, 4, 5)
Cube = 12, Triple = (6, 8, 10)
Cube = 18, Triple = (2, 12, 16)
Cube = 18, Triple = (9, 12, 15)
Cube = 19, Triple = (3, 10, 18)
Cube = 20, Triple = (7, 14, 17)
Cube = 24, Triple = (12, 16, 20)

Added by:Wanderley Guimarăes
Date:2006-06-01
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:ACM Mid Central Regionals 1995

hide comments
2010-06-25 23:18:37 Abdelrahman Hatem
@Mahaboob Ali
but i think it was written up a,b,c>1
2010-06-19 10:12:53 Mahaboob Ali
Why,
Cube = 9, Triple = (1,6,8)
is not there in the first part of output ?
2010-04-27 04:57:47 numerix
Then print it out and submit as TEXT ...
2010-04-26 22:57:10 islCodr
Wondering if it be completed with Python? I have a solution that runs a ~.5 sec on my Dell laptop. But, fails with TLE.
2009-08-13 06:17:15 Juan Bustos
Hurray for Andrew Wiles!
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