#include <cstdio>
#include <cstdlib>
#include <algorithm>
using namespace std;

#define leftSon (node << 1)
#define rightSon ((node << 1) + 1)
#define nmax 800010

int AInt[nmax], N, M, T, A, B, X, sol, pos, value, start, end;

void Update(int node, int left, int right;
void Query(int node, int left, int right);

int main()
{
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    int i;
    scanf("%i %i", &N, &M);
    for(i = 1; i <= N; i++)
    {
          scanf("%i", &X);
          pos = i, value = X;
          Update(1, 1, N, i, X);
    }
    for(; M; M --)
    {
          scanf("%i %i %i", &T, &A, &B);
          if(T)
          {
               pos = A, value = B;
               Update(1, 1, N, A, B);
          }else
          {
              sol = 0, start = A, end = B;
              Query(1, 1, N, A, B);
              printf("%i\n", sol);
          }
    }
    return 0;
}

void Update(int node, int left, int right)
{
     if(left == right)
     {
             AInt[node] = value;
             return ;
     }
     int mid = (left + right) >> 1;
     if(pos <= mid) Update(leftSon, left, mid);
     else Update(rightSon, mid + 1, right);
     AInt[node] = max(AInt[leftSon], AInt[rightSon]);
}

void Query(int node, int left, int right)
{
     if(start <= left && right <= end)
     {
              sol = max(sol, AInt[node]);
              return ;
     }
     int mid = (left + right) >> 1;
     if(start <= mid) Query(leftSon, left, mid);
     if(mid < end) Query(rightSon, mid + 1, right);
}