#include<cstdio>
#include<string>

using namespace std;

#ifdef HOME
const string inputFile = "input.txt";
const string outputFile = "output.txt";
#else
const string problemName = "arbint";
const string inputFile = problemName + ".in";
const string outputFile = problemName + ".out";
#endif

const int NMAX = 100000 + 5;

int N, M;
int A[NMAX];
int AI[4 * NMAX];

void build(int nod, int lo, int hi) {
    if(lo == hi) {
        AI[nod] = A[lo];
        return;
    }

    int mi = (lo + hi) / 2;

    build(2 * nod + 0, lo, mi + 0);
    build(2 * nod + 1, mi + 1, hi);

    AI[nod] = max(AI[2 * nod + 0], AI[2 * nod + 1]);
}

void update(int nod, int lo, int hi, int poz, int val) {
    if(lo == hi) {
        AI[nod] = val;
        A[poz] = val;
        return;
    }

    int mi = (lo + hi) / 2;

    if(poz <= mi)
        update(2 * nod + 0, lo, mi + 0, poz, val);
    else
        update(2 * nod + 1, mi + 1, hi, poz, val);

    AI[nod] = max(AI[2 * nod + 0], AI[2 * nod + 1]);
}

int query(int nod, int lo, int hi, int L, int R) {
    if(L <= lo && hi <= R)
        return AI[nod];

    if(R < lo || hi < L)
        return -1;

    int mi = (lo + hi) / 2;

    int q1 = query(2 * nod + 0, lo, mi + 0, L, R);
    int q2 = query(2 * nod + 1, mi + 1, hi, L, R);

    return max(q1, q2);
}

int main() {
    int i, t, x, y;

    freopen(inputFile.c_str(), "r", stdin);
    freopen(outputFile.c_str(), "w", stdout);

    scanf("%d%d", &N, &M);

    for(i = 1; i <= N; i++)
        scanf("%d", &A[i]);

    build(1, 1, N);

    while(M--) {
        scanf("%d%d%d", &t, &x, &y);

        if(t)
            update(1, 1, N, x, y);
        else
            printf("%d\n", query(1, 1, N, x, y));
    }

    return 0;
}