CF1421C.Palindromifier

普及/提高-

通过率:0%

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题目描述

Ringo found a string ss of length nn in his yellow submarine. The string contains only lowercase letters from the English alphabet. As Ringo and his friends love palindromes, he would like to turn the string ss into a palindrome by applying two types of operations to the string.

The first operation allows him to choose ii ( 2in12 \le i \le n-1 ) and to append the substring s2s3sis_2s_3 \ldots s_i ( i1i - 1 characters) reversed to the front of ss .

The second operation allows him to choose ii ( 2in12 \le i \le n-1 ) and to append the substring sisi+1sn1s_i s_{i + 1}\ldots s_{n - 1} ( nin - i characters) reversed to the end of ss .

Note that characters in the string in this problem are indexed from 11 .

For example suppose s=s= abcdef. If he performs the first operation with i=3i=3 then he appends cb to the front of ss and the result will be cbabcdef. Performing the second operation on the resulted string with i=5i=5 will yield cbabcdefedc.

Your task is to help Ringo make the entire string a palindrome by applying any of the two operations (in total) at most 3030 times. The length of the resulting palindrome must not exceed 10610^6

It is guaranteed that under these constraints there always is a solution. Also note you do not have to minimize neither the number of operations applied, nor the length of the resulting string, but they have to fit into the constraints.

输入格式

The only line contains the string SS ( 3s1053 \le |s| \le 10^5 ) of lowercase letters from the English alphabet.

输出格式

The first line should contain kk ( 0k300\le k \le 30 ) — the number of operations performed.

Each of the following kk lines should describe an operation in form L i or R i. LL represents the first operation, RR represents the second operation, ii represents the index chosen.

The length of the resulting palindrome must not exceed 10610^6 .

输入输出样例

  • 输入#1

    abac

    输出#1

    2
    R 2
    R 5
  • 输入#2

    acccc

    输出#2

    2
    L 4
    L 2
  • 输入#3

    hannah

    输出#3

    0

说明/提示

For the first example the following operations are performed:

abac \to abacab \to abacaba

The second sample performs the following operations: acccc \to cccacccc \to ccccacccc

The third example is already a palindrome so no operations are required.

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