#include <fstream>
#define DIM 100010

using namespace std;

int A[4*DIM];
int n, m, i, a, b, sol, x, t;

inline int maxim(int a, int b) {
    return ( a>b ? a : b );
}

void update(int nod, int st, int dr, int p, int v) {
    if (st == dr) {
        A[nod] = v;
        return;
    }
    int m = (st + dr)/2;
    if (p <= m)
        update(2*nod, st, m, p, v);
    if (p>m)
        update(2*nod+1, m+1, dr, p, v);

    A[nod] = maxim(A[2*nod], A[2*nod+1]);
}

int query(int nod, int st, int dr, int a, int b) {
    if (a<=st && b>=dr){
        sol = maxim(sol, A[nod]);
        return A[nod];
    }

    int mst = 0, mdr = 0, m = (st+dr)/2;
    if (a<=m)
        mst = query(2*nod, st, m, a, b);
    if (b > m)
        mdr = query(2*nod+1, m+1, dr, a, b);
    return maxim(mst, mdr);
}

int main() {
    ifstream fin("arbint.in");
    ofstream fout("arbint.out");
    fin>>n>>m;
    for (i=1;i<=n;i++) {
        fin>>x;
        update(1, 1, n, i, x);
    }
    for (i=1;i<=m;i++) {
        fin>>t>>a>>b;
        if (t == 0) {
            sol = 0;
            query(1,1,n,a,b);
            fout<<sol<<"\n";
        }
        else
            update(1,1,n,a,b);
    }

    return 0;
}