A10254. Longest k-Good Segment

The array $a$ with $n$ integers is given. Let's call the sequence of one or more consecutive elements in $a$ segment. Also let's call the segment k-good if it contains no more than $k$ different values.

Find any longest k-good segment.

As the input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use scanf/printf instead of cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.

The first line contains two integers $n,k$ ( $1<=k<=n<=5·10^{5}$ ) — the number of elements in $a$ and the parameter $k$ .

The second line contains $n$ integers $a_{i}$ ( $0<=a_{i}<=10^{6}$ ) — the elements of the array $a$ .

Print two integers $l,r$ ( $1<=l<=r<=n$ ) — the index of the left and the index of the right ends of some k-good longest segment. If there are several longest segments you can print any of them. The elements in $a$ are numbered from $1$ to $n$ from left to right.