CF615C.Running Track

普及/提高-

通过率:0%

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题目描述

A boy named Ayrat lives on planet AMI-1511. Each inhabitant of this planet has a talent. Specifically, Ayrat loves running, moreover, just running is not enough for him. He is dreaming of making running a real art.

First, he wants to construct the running track with coating tt . On planet AMI-1511 the coating of the track is the sequence of colored blocks, where each block is denoted as the small English letter. Therefore, every coating can be treated as a string.

Unfortunately, blocks aren't freely sold to non-business customers, but Ayrat found an infinite number of coatings ss . Also, he has scissors and glue. Ayrat is going to buy some coatings ss , then cut out from each of them exactly one continuous piece (substring) and glue it to the end of his track coating. Moreover, he may choose to flip this block before glueing it. Ayrat want's to know the minimum number of coating ss he needs to buy in order to get the coating tt for his running track. Of course, he also want's to know some way to achieve the answer.

输入格式

First line of the input contains the string ss — the coating that is present in the shop. Second line contains the string tt — the coating Ayrat wants to obtain. Both strings are non-empty, consist of only small English letters and their length doesn't exceed 21002100 .

输出格式

The first line should contain the minimum needed number of coatings nn or -1 if it's impossible to create the desired coating.

If the answer is not -1, then the following nn lines should contain two integers xix_{i} and yiy_{i} — numbers of ending blocks in the corresponding piece. If xi<=yix_{i}<=y_{i} then this piece is used in the regular order, and if x_{i}>y_{i} piece is used in the reversed order. Print the pieces in the order they should be glued to get the string tt .

输入输出样例

  • 输入#1

    abc
    cbaabc
    

    输出#1

    2
    3 1
    1 3
    
  • 输入#2

    aaabrytaaa
    ayrat
    

    输出#2

    3
    1 1
    6 5
    8 7
    
  • 输入#3

    ami
    no
    

    输出#3

    -1
    

说明/提示

In the first sample string "cbaabc" = "cba" + "abc".

In the second sample: "ayrat" = "a" + "yr" + "at".

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