[HDOJ5451] Best Solver (WTF)

Title: http://acm.hdu.edu.cn/showproblem.php?pid=5451

Analysis: a=5+2 Radical root 6 b=6-2 square root 6

N=1+2^x

So A^n+b^n is an integer.

Notice the 0<b^n<1

So ans=a^n+b^n-1

The result form is similar to the Fibonacci structure.

So construct an=p*an-1+q*an-2

Inverse feature root get recursive an=10* (an-1)-(an-2)

N is too large to be able to quickly power a matrix

Note M is very small, so the mold comes out certainly has the circulation section, the link biggest is also m*m, can withstand

Finally, the problem of the 1+2^x membrane Circulation Festival, the rapid Power solution

[HDOJ5451] Best Solver (WTF)