Background

Have you ever had a dream like this?

Beside me, there is a girl I have never met before.

I like her a lot, and she likes me a lot too.

But—

In the end, it is always

When she is taken away by the sky,

That I wake up from the dream.

Human?

No.

Not human.

No one would...

Have wings.

No, no, no.

There is nowhere.

There is nowhere I can go back to.

I have no place I can go back to!

Nowhere...

A place I can go back to... anywhere... nowhere at all...

I do not want to kill anyone, and I do not want to hurt anyone!

Why... why did you create me...

No need... I do not need this kind of power...

“Happiness” is not enough to describe how I feel right now.

What should I say?

Ah, right.

I... love you.

I love you... Master.

In Greek mythology, Icarus flew too close to the sun; the feathers glued on with wax melted, and he fell into the sea and died.

Problem Description

Icarus gives you a sequence $a$ of length $n$.

You need to process $m$ operations. There are two types of operations:

1. Change the value of every element equal to $x$ in the sequence to $y$.
2. Find a position $i$ such that $a_i=x$ and a position $j$ such that $a_j=y$, so that $|i-j|$ is minimized, and output $|i-j|$.

Input Format

The first line contains two integers $n,m$.

The next line contains $n$ integers, representing the sequence $a$.

Then follow $m$ lines, each containing three numbers $opt,x,y$.

If $opt$ is $1$, it means changing the value at every position with value $x$ to $y$.

If $opt$ is $2$, it means finding a position $i$ such that $a_i=x$ and a position $j$ such that $a_j=y$ to minimize $|i-j|$, and output $|i-j|$. If no such positions can be found, output Ikaros.

This problem is strictly online. For each operation, $x,y$ need to be xor-ed with the answer from two queries ago. If the output is Ikaros, or if it is the first query, then the last answer is $0$.

There are $50$ test cases in total, and it is guaranteed that $n=m$.

Output Format

For each operation of type $2$, output one line with an integer representing the answer.

If it is impossible to find $i,j$ that satisfy the statement, output Ikaros.

5 5
1 2 2 4 4
2 3 3
2 2 4
1 3 2
1 5 5
2 2 5

Ikaros
1
1

Hint

Idea: nzhtl1477, Solution: nzhtl1477, Code: nzhtl1477, Data: nzhtl1477 ( partially uploaded ).

Constraints: For $100\%$ of the testdata, all numbers are within $[1,10^5]$, and the value in each operation does not exceed $n$.

Translated by ChatGPT 5