存档

后缀数组：http://www.cnblogs.com/staginner/archive/2012/02/02/2335600.html

分块：http://97littleleaf11.xyz/oi/divide_into_block/

top-tree：http://www.cnblogs.com/clrs97/p/4403244.html

fhp_treap:http://memphis.is-programmer.com/posts/46317.html

FFT：http://blog.miskcoo.com/2015/04/polynomial-multiplication-and-fast-fourier-transform#i-15