#include <cstdio>

using namespace std;

#define BS 512
#define BC 256

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

struct Bucket {
    int B[BS];
    bool updated;
    int maxv, sz;

    int& operator[](int poz) {
        return B[poz];
    }

    void Rebuild() {
        maxv = 0;
        for(int i=0; i<sz; i++)
            maxv = max(maxv, B[i]);
        updated = true;
    }

    int getMax() {
        if(!updated) Rebuild();
        return maxv;
    }
};
Bucket B[BC];

void Update(int poz, int val) {
    B[poz / BS][poz % BS] = val;
    B[poz / BS].updated = false;
}

int Query(int a, int b) {
    int i=a, bi, rez = 0;

    for(bi=i/BS; i%BS && i<=b; i++)
        rez = max(rez, B[bi][i % BS]);
    for(bi=i/BS;i+BS-1<=b; i+=BS, bi++)
        rez = max(rez, B[bi].getMax());
    for(bi=i/BS; i<=b; i++)
        rez = max(rez, B[bi][i % BS]);

    return rez;
}

int main() {
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);

    int n, m, t, a, b;
    scanf("%d%d", &n, &m);

    B[0].sz = 1;
    for(int i=1; i<=n; i++) {
        scanf("%d", &a);
        B[i / BS].sz ++;
        Update(i, a);
    }

    while(m--) {
        scanf("%d%d%d", &t, &a, &b);
        if(t == 1) Update(a, b);
        else printf("%d\n", Query(a, b));
    }

    return 0;
}