#include<bits/stdc++.h>
#define maxn 200001
#define ls(x) (x<<1)
#define rs(x) (x<<1|1)
using namespace std;
int tree[16*maxn],num[maxn],n,m;
int build(int l,int r,int id){
	if (l==r) return tree[id]=num[l];
	int mid=(l+r)>>1,p=0;
	p=max(p,build(l,mid,ls(id)));
	p=max(p,build(mid+1,r,rs(id)));
	return tree[id]=p;
}
int update(int n,int k,int l,int r,int id){
	if (l==r || tree[id]<k) return tree[id]=k;
	int mid=(l+r)>>1;
	if (n<=mid) tree[id]=max(tree[id],update(n,k,l,mid,ls(id)));
	else tree[id]=max(tree[id],update(n,k,mid+1,r,rs(id)));
	return tree[id];
}
int query(int a,int b,int l,int r,int id){
	if (l==r || (a<=l && b>=r)) return tree[id];
	int mid=(l+r)>>1,p=0;
	if (a<=mid) p=max(p,query(a,b,l,mid,ls(id)));
	if (b>mid) p=max(p,query(a,b,mid+1,r,rs(id)));
	return p;
}
int main(){
	scanf("%d%d",&n,&m);
	for (int i=1;i<=n;i++) scanf("%d",&num[i]);
	build(1,n,1);
	char op;
	int a,b;
	for (int i=1;i<=m;i++){
		cin>>op>>a>>b;
		if (op=='Q') printf("%d\n",query(a,b,1,n,1));
		else if (query(a,a,1,n,1)<b) update(a,b,1,n,1);
	}
	return 0;
}