Problem:
Score : 100 points

Problem Statement

You are given an array a_0, a_1, ..., a_{N-1} of length N. Process Q queries of the following types.

The type of i-th query is represented by T_i.

T_i=1: You are given two integers X_i,V_i. Replace the value of A_{X_i} with V_i.

T_i=2: You are given two integers L_i,R_i. Calculate the maximum value among A_{L_i},A_{L_i+1},\cdots,A_{R_i}.

T_i=3: You are given two integers X_i,V_i. Calculate the minimum j such that X_i \leq j \leq N, V_i \leq A_j. If there is no such j, answer j=N+1 instead.

Constraints

1 \leq N \leq 2 \times 10^5

0 \leq A_i \leq 10^9

1 \leq Q \leq 2 \times 10^5

1 \leq T_i \leq 3

1 \leq X_i \leq N, 0 \leq V_i \leq 10^9 (T_i=1,3)

1 \leq L_i \leq R_i \leq N (T_i=2)

All values in Input are integer.

Input

Input is given from Standard Input in the following format:

N Q
A_1 A_2 \cdots A_N
First query
Second query
\vdots
Q-th query

Each query is given in the following format:

If T_i=1,3,

T_i X_i V_i

If T_i=2,

T_i L_i R_i

Output

For each query with T_i=2, 3, print the answer.

Sample Input 1

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

Sample Output 1

3
3
2
6

First query: Print 3, which is the maximum of (A_1,A_2,A_3,A_4,A_5)=(1,2,3,2,1).

Second query: Since 3>A_2, j=2 does not satisfy the condition．Since 3 \leq A_3, print j=3.

Third query: Replace the value of A_3 with 1. It becomes A=(1,2,1,2,1).

Fourth query: Print 2, which is the maximum of (A_2,A_3,A_4)=(2,1,2).

Fifth query: Since there is no j that satisfies the condition, print j=N+1=6.

Solution in PyPy3 (7.3.0) (judge verdict: Accepted)

import sys
input = lambda: sys.stdin.readline().rstrip()

class LazySegmentTree():
    def __init__(self, init, unitX, unitA, f, g, h):
        self.f = f # (X, X) -> X
        self.g = g # (X, A, size) -> X
        self.h = h # (A, A) -> A
        self.unitX = unitX
        self.unitA = unitA
        self.f = f
        if type(init) == int:
            self.n = init
            self.n = 1 << (self.n - 1).bit_length()
            self.X = [unitX] * (self.n * 2)
            self.size = [1] * (self.n * 2)
        else:
            self.n = len(init)
            self.n = 1 << (self.n - 1).bit_length()
            self.X = [unitX] * self.n + init + [unitX] * (self.n - len(init))
            self.size = [0] * self.n + [1] * len(init) + [0] * (self.n - len(init))
            for i in range(self.n-1, 0, -1):
                self.X[i] = self.f(self.X[i*2], self.X[i*2|1])
    
        for i in range(self.n - 1, 0, -1):
            self.size[i] = self.size[i*2] + self.size[i*2|1]
        
        self.A = [unitA] * (self.n * 2)
        
    def update(self, i, x):
        i += self.n
        self.X[i] = x
        i >>= 1
        while i:
            self.X[i] = self.f(self.X[i*2], self.X[i*2|1])
            i >>= 1
    
    def calc(self, i):
        return self.g(self.X[i], self.A[i], self.size[i])
    
    def calc_above(self, i):
        i >>= 1
        while i:
            self.X[i] = self.f(self.calc(i*2), self.calc(i*2|1))
            i >>= 1
    
    def propagate(self, i):
        self.X[i] = self.g(self.X[i], self.A[i], self.size[i])
        self.A[i*2] = self.h(self.A[i*2], self.A[i])
        self.A[i*2|1] = self.h(self.A[i*2|1], self.A[i])
        self.A[i] = self.unitA
        
    def propagate_above(self, i):
        H = i.bit_length()
        for h in range(H, 0, -1):
            self.propagate(i >> h)
    
    def propagate_all(self):
        for i in range(1, self.n):
            self.propagate(i)
    
    def getrange(self, l, r):
        l += self.n
        r += self.n
        l0, r0 = l // (l & -l), r // (r & -r) - 1
        self.propagate_above(l0)
        self.propagate_above(r0)
        
        al = self.unitX
        ar = self.unitX
        while l < r:
            if l & 1:
                al = self.f(al, self.calc(l))
                l += 1
            if r & 1:
                r -= 1
                ar = self.f(self.calc(r), ar)
            l >>= 1
            r >>= 1
        return self.f(al, ar)
    
    def getvalue(self, i):
        i += self.n
        self.propagate_above(i)
        return self.calc(i)
    
    def operate_range(self, l, r, a):
        l += self.n
        r += self.n
        l0, r0 = l // (l & -l), r // (r & -r) - 1
        self.propagate_above(l0)
        self.propagate_above(r0)
        while l < r:
            if l & 1:
                self.A[l] = self.h(self.A[l], a)
                l += 1
            if r & 1:
                r -= 1
                self.A[r] = self.h(self.A[r], a)
            l >>= 1
            r >>= 1
        
        self.calc_above(l0)
        self.calc_above(r0)
    
    # Find r s.t. calc(l, ..., r-1) = True and calc(l, ..., r) = False
    def max_right(self, l, z):
        if l >= self.n: return self.n
        l += self.n
        s = self.unitX
        while 1:
            while l % 2 == 0:
                l >>= 1
            if not z(self.f(s, self.calc(l))):
                while l < self.n:
                    l *= 2
                    if z(self.f(s, self.calc(l))):
                        s = self.f(s, self.calc(l))
                        l += 1
                return l - self.n
            s = self.f(s, self.calc(l))
            l += 1
            if l & -l == l: break
        return self.n
    
    # Find l s.t. calc(l, ..., r-1) = True and calc(l-1, ..., r-1) = False
    def min_left(self, r, z):
        if r <= 0: return 0
        r += self.n
        s = self.unitX
        while 1:
            r -= 1
            while r > 1 and r % 2:
                r >>= 1
            if not z(self.f(self.calc(r), s)):
                while r < self.n:
                    r = r * 2 + 1
                    if z(self.f(self.calc(r), s)):
                        s = self.f(self.calc(r), s)
                        r -= 1
                return r + 1 - self.n
            s = self.f(self.calc(r), s)
            if r & -r == r: break
        return 0

f = lambda x, y: max(x, y)
g = lambda x, a, s: max(x, a)
h = lambda a, b: max(a, b)
unitX = 0
unitA = 0
N, Q = map(int, input().split())
A = [int(a) for a in input().split()]
st = LazySegmentTree(A, unitX, unitA, f, g, h)

for _ in range(Q):
    t, a, b = map(int, input().split())
    if t == 1:
        st.update(a-1, b)
    elif t == 2:
        print(st.getrange(a-1, b))
    else:
        z = lambda x: x < b
        print(min(N, st.max_right(a-1, z)) + 1)