#include <bits/stdc++.h>

#define BUFFER_SIZE 1 << 8
#define DIM 100005

int a[4 * DIM];

inline int read() {
	int n = 0;
	char c = getchar_unlocked();

	while (!('0' <= c && c <= '9')) {
		c = getchar_unlocked();
	}

	while ('0' <= c && c <= '9') {
		n = n * 10 + c - '0';
		c = getchar_unlocked();
	}

	return n;
}

inline void print(int n) {
	char snum[BUFFER_SIZE];
	int i = 0;

	do {
		snum[i++] = n % 10 + '0';
		n /= 10;
	} while (n);

	--i;

	while (i >= 0) {
		putchar(snum[i--]);
	}

	putchar('\n');
}

void update(int node, int left, int right, int value, int position) {
	if (left == right) {
		a[node] = value;
		return;
	}

	int mid = left + (right - left) / 2;

	if (position <= mid) {
		update(2 * node, left, mid, value, position);
	} else {
		update(2 * node + 1, mid + 1, right, value, position);
	}

	a[node] = std::max(a[2 * node], a[2 * node + 1]);
}

void query(int node, int left, int right, int start, int end, int &maxim) {
	if (start <= left && right <= end) {
		if (maxim < a[node]) {
			maxim = a[node];
		}
		return;
	}

	int mid = left + (right - left) / 2;

	if (start <= mid) {
		query(2 * node, left, mid, start, end, maxim);
	}

	if (mid < end) {
		query(2 * node + 1, mid + 1, right, start, end, maxim);
	}
}

int main() {
	freopen("arbint.in", "r", stdin);
	freopen("arbint.out", "w", stdout);
	int N, M, X, A, B, position, value, maxim, start, end;
	N = read(), M = read();

	for (int i = 1 ; i <= N ; ++i) {
		X = read();
		position = i;
		value = X;
		update(1, 1, N, value, position);
	}

	for (; M ; --M) {
		X = read(), A = read(), B = read();

		if (X == 0) {
			maxim = -1;
			start = A, end = B;
			query(1, 1, N, start, end, maxim);
			print(maxim);
		} else {
			position = A, value = B;
			update(1, 1, N, value, position);
		}
	}

	return 0;
}