#include <cstdio>
#include <algorithm>
#include <vector>
#include <cmath>
#include <queue>
#include <stack>
#include <set>
#include <iomanip>
#include <cstring>

#define NMax 500005
using namespace std;

int n,m,x,sol,q,a,b;
int ARB[NMax];
void update(int nod,int st, int dr,int poz,int val){
    if(st == dr){
        ARB[nod] = val;
        return;
    }
    int m = (st + dr) / 2;
    if(poz <= m)
        update(2 * nod, st, m, poz, val);
    else
        update(2 * nod + 1, m + 1, dr, poz, val);
    ARB[nod] = max(ARB[2 * nod], ARB[2 * nod + 1]);
}
void query(int nod,int st, int dr, int a, int b){
    if(a <= st && b >= dr){
        sol = max(sol, ARB[nod]);
        return;
    }
    int m = (st + dr) / 2;
    if(a <= m)
        query(2 * nod, st, m, a, b);
    if(m < b)
        query(2 * nod + 1, m + 1, dr, a, b);
}
int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(int i = 1; i <= n; ++i){
        scanf("%d",&x);
        update(1,1,n,i,x);
    }
    for(int i = 1; i <= m; ++i){
        scanf("%d%d%d",&q,&a,&b);
        if(q == 1)
            update(1,1,n,a,b);
        else{
            sol = 0 ;
            query(1,1,n,a,b);
            printf("%d\n",sol);
        }
    }
    return 0;
}