Introduction - If you have any usage issues, please Google them yourself
A given S = {a1, a2, a3, ..., an}, if P = {a_x1, a_x2, a_x3, ..., a_xm}, satisfy (x1 < x2 < ... < xm) and (ax1 < ax2 < ... < axm), called P S in a rising sequence. If you have multiple P satisfy the condition, then we would like to seek the lexicographical smallest.