B. Letter Exchangetime limit per test4 secondsmemory limit per test512 megabytesinputstandard inputoutputstandard outputA cooperative game is played by m people. In the game, there are 3m sheets of paper: m sheets with letter 'w', m sheets with letter 'i', and m sheets with letter 'n'.Initially, each person is given three sheets (possibly with equal letters).The goal of the game is to allow each of the m people to spell the word "win" using their sheets of paper. In other words, everyone should have one sheet with letter 'w', one sheet with letter 'i', and one sheet with letter 'n'.To achieve the goal, people can make exchanges. Two people participate in each exchange. Both of them choose exactly one sheet of paper from the three sheets they own and exchange it with each other.Find the shortest sequence of exchanges after which everyone has one 'w', one 'i', and one 'n'.InputEach test contains multiple test cases. The first line contains the number of test cases t (1 \le t \le 10^4). The description of the test cases follows.The first line of each test case contains a single integer m (2 \le m \le 10^5) — the number of people.The i-th of the next m lines contains a string s_i of length 3 consisting of lowercase English letters 'w', 'i', and 'n', denoting the letters person i has on their sheets of paper at the beginning of the game, in arbitrary order.Each of the letters 'w', 'i', and 'n' appears on the sheets of paper exactly m times in total.It is guaranteed that the sum of m over all test cases does not exceed 10^5.OutputFor each test case, print a non-negative integer k — the smallest number of exchanges people need to make everyone have one 'w', one 'i', and one 'n'.In each of the next k lines print four tokens a_1 c_1 a_2 c_2, describing the exchanges in chronological order (1 \le a_1, a_2 \le m; a_1 \ne a_2; c_1, c_2 are one of \{\mathtt{w}, \mathtt{i}, \mathtt{n}\}): person a_1 gives letter c_1 to person a_2, while person a_2 gives letter c_2 to person a_1 at the same time.If there are multiple solutions, print any.ExampleInput
32nwiinw3innnwwwii4winwwwiiinnnOutput
0
2
2 w 3 i
3 w 1 n
3
2 w 3 i
2 w 4 n
3 i 4 n

32nwiinw3innnwwwii4winwwwiiinnn
0 2 2 w 3 i 3 w 1 n 3 2 w 3 i 2 w 4 n 3 i 4 n 
['constructive algorithms', '*1900']