#include<cstdio>
    #include<iostream>
    using namespace std;
    #define MAX 300001
    int N , M , v[MAX] , A[2*MAX] , maxx;

    void build(int n, int l , int r);
    void query(int n, int l , int r , int a, int b);
    void update(int n , int l , int r ,int poz , int val);

    int main()
    {
        int a , b , t;
        freopen("arbint.in" , "r" , stdin );
        freopen("arbint.out" , "w" , stdout );
        scanf("%d%d" , &N , &M );
        for(int i = 1 ; i <= N ; ++i )
            scanf("%d" , &v[i]);
        build(1,1,N);
        for(int i = 1 ; i <= M ; ++i )
        {
            maxx = -1;
            scanf("%d%d%d" , &t , &a , &b);
            if(t == 0)
            {
                   query(1,1,N,a,b);
                   printf("%d\n" , maxx );
            }
            else update(1,1,N,a,b);
        }
        return 0;
    }

    void build(int n , int l , int r)
    {
        if(l == r)A[n] = v[l];
        else
        {
            int m = (l+r)/2;
            build(2*n,l,m);
            build(2*n+1,m+1,r);
            A[n] = max(A[2*n],A[2*n+1]);
        }
    }

    void query(int n , int l , int r , int a , int b)
    {
        if(a <= l && b >= r)maxx = max(maxx,A[n]);
        else
        {
            int m = (l+r)/2;
            if(a <= m)
                query(2*n,l,m,a,b);
            if(b > m)
                query(2*n+1,m+1,r,a,b);
        }
    }

    void update(int n , int l , int r , int a , int b)
    {
        if(l == r)A[n] = b;
        else
        {
            int m = (l+r)/2;
            if(a <= m)
                update(2*n,l,m,a,b);
            else
                update(2*n+1,m+1,r,a,b);
            A[n] = max(A[2*n],A[2*n+1]);
        }
    }