#include <fstream>
#define DIM 300000
#define INF 2000000000

using namespace std;

int A[DIM];
int n, a, b, p, v, i, q, 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)
        return A[nod];
    int m = (st + dr)/2;
    int stanga = -INF;
    int dreapta = -INF;
    if (a <= m)
        stanga = query(2*nod, st, m, a, b);
    if (b>=m+1)
        dreapta = query(2*nod+1, m+1, dr, a, b);
    return maxim(stanga, dreapta);
}

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


    return 0;
}