#include <cstdio>
#include <algorithm>

#define Nmax 4 * 100005
#define INF 0x3f3f3f3f;

using namespace std;
int x,st,dr,ind,ans;
int range[ Nmax ];

void scan(int &A)
{
    char c = 0; A = 0;
    do
    {
        c = fgetc(stdin);
        if('0' <= c && c <= '9')
            A = A * 10 + c - 48;
    } while('0' <= c && c <= '9');
}

void Update(int li,int lf,int pz)
{
    if(li == lf)
    {
        range[ pz ] = x;
        return;
    }
    int m = li +((lf-li)>>1);
    if(ind <= m) Update(li,m,pz<<1);
    else Update(m+1,lf,(pz<<1)+1);
    range[ pz ] = max ( range[pz << 1] , range[(pz<<1) + 1]);
}

void Querry(int li,int lf,int pz)
{
    if(st <= li && lf <= dr)
    {
        ans = max(ans,range[ pz ]);
        return;
    }
    int m = li + ((lf-li)>>1);
    if(st <= m) Querry(li,m,pz<<1);
    if(dr > m) Querry(m+1,lf,(pz<<1)+1);
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int N,M,op;
    scan(N),scan(M);
    for(int i = 1; i <= N; ++i)
    {
        ind = i;
        scan(x);
        Update(1,N,1);
    }
    for(int i = 1; i <= M; ++i)
    {
        scan(op);
        if(op == 0)
        {
            ans = -INF;
            scan(st),scan(dr);
            Querry(1,N,1);
            printf("%d\n",ans);
        }
        else
        {
            scan(ind),scan(x);
            Update(1,N,1);
        }
    }

    return 0;
}