#include<cstdio>
#include<algorithm>
using namespace std;
#define MAX 4*100001+100
#define oo 0x3f3f3f3f
int arb[MAX];
int N,M,poz,val,a,b,maxAB;
void Update(int nod,int left,int right){
    int mid;
    if(left==right){//interval format dintr-un singur nod
        arb[nod]=val;
        return;
    }
        mid=(left+right)/2;
        if(poz<=mid)
            Update(2*nod,left,mid);
        else
            Update((2*nod)+1,mid+1,right);
        arb[nod]=max(arb[2*nod],arb[(2*nod)+1]);
}
void FindMaxAB(int nod,int left,int right){
    int mid;
    if(a<=left && right<=b){
        if(arb[nod]>maxAB){
            maxAB=arb[nod];
        }
        return;
    }
        mid=(left+right)/2;
        if(a<=mid)FindMaxAB(2*nod,left,mid);
        if(b>mid) FindMaxAB(2*nod+1,mid+1,right);
}
int main(){
    int i,x,p,q;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&N,&M);
    for(i=1;i<=N;i++){
        scanf("%d",&x);
        val=x;poz=i;
        Update(1,1,N);
    }
    for(i=1;i<=M;i++){
        scanf("%d",&x);
        if(x){
            scanf("%d%d",&p,&q);
            poz=p;val=q;
            Update(1,1,N);
        }
        else{
            scanf("%d%d",&a,&b);
            maxAB=-oo;
            FindMaxAB(1,1,N);
            printf("%d\n",maxAB);
        }
    }
    fclose(stdin);
    fclose(stdout);
    return 0;
}