GukiZ and GukiZiana

题面翻译

给定一个数列$a_1,a_2,\dots,a_n$，有两个操作：

1. 给定$l,r,x$，令$a_l,a_{l+1},\dots,a_r$都加上$x$。
2. 给定$y$,求一个最大的$j-i$，满足$a_i=a_j=y$，输出最大的$j-i$，无解输出$-1$。

题目描述

Professor GukiZ was playing with arrays again and accidentally discovered new function, which he called $GukiZiana$ . For given array $a$ , indexed with integers from $1$ to $n$ , and number $y$ , $GukiZiana(a,y)$ represents maximum value of $j-i$ , such that $a_{j}=a_{i}=y$ . If there is no $y$ as an element in $a$ , then $GukiZiana(a,y)$ is equal to $-1$ . GukiZ also prepared a problem for you. This time, you have two types of queries:

1. First type has form $1$ $l$ $r$ $x$ and asks you to increase values of all $a_{i}$ such that $l<=i<=r$ by the non-negative integer $x$ .
2. Second type has form $2$ $y$ and asks you to find value of $GukiZiana(a,y)$ .

For each query of type $2$ , print the answer and make GukiZ happy!

输入格式

The first line contains two integers $n$ , $q$ ( $1<=n<=5*10^{5},1<=q<=5*10^{4}$ ), size of array $a$ , and the number of queries.

The second line contains $n$ integers $a_{1},a_{2},...\ a_{n}$ ( $1<=a_{i}<=10^{9}$ ), forming an array $a$ .

Each of next $q$ lines contain either four or two numbers, as described in statement:

If line starts with $1$ , then the query looks like $1$ $l$ $r$ $x$ ( $1<=l<=r<=n$ , $0<=x<=10^{9}$ ), first type query.

If line starts with $2$ , then th query looks like $2$ $y$ ( $1<=y<=10^{9}$ ), second type query.

输出格式

For each query of type $2$ , print the value of $GukiZiana(a,y)$ , for $y$ value for that query.

样例 #1

样例输入 #1

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

样例输出 #1

2

样例 #2

样例输入 #2

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

样例输出 #2

0
-1