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#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;
typedef int ll;
const int maxn = 1e5 + 10;
const int INF = 2e9;
int arr[maxn];
pair segment_tree[3 * maxn];
pair merged_nodes(pair  A, pair B) {
    vector v = {A.first, A.second, B.first, B.second};
    sort(v.begin(), v.end());
    return make_pair(v[2], v[3]);
}
void build_tree(int L, int R, int position) {
    if(L == R) {
        segment_tree[position] = make_pair(arr[L], -INF);
    }
    else {
        int middle = (L + R) / 2;
        build_tree(L, middle, 2 * position);
        build_tree(middle + 1, R,  2 * position + 1);
        segment_tree[position] = merged_nodes(segment_tree[2 * position], segment_tree[2 * position + 1]);
    }
}
// L R i L R j L R
pair query(int L, int R, int position, int i, int j) {
    if(i <= L and R <= j) {
        return segment_tree[position];
    }
    if(R < i or j < L) {
        return make_pair(-INF, -INF);
    }
    int middle = (L + R) / 2;
    return merged_nodes(query(L, middle, 2 * position, i, j), query(middle + 1, R, 2 * position + 1, i, j));
}
void update(int L, int R, int position, int idx, int new_value) {
    if(L == R) {
        segment_tree[position] = make_pair(new_value, -INF);
        return;
    }
    int middle = (L + R) / 2;
    if(idx <= middle) {
        update(L, middle, 2 * position, idx, new_value);
    }
    else {
        update(middle + 1, R, 2 * position + 1, idx, new_value);
    }
    segment_tree[position] = merged_nodes(segment_tree[2 * position], segment_tree[2 * position + 1]);
}
int main(){
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n;
    for(int i = 0; i < n; i++) {
        cin >> arr[i];
    }
    build_tree(0, n - 1, 1);
    int q;
    cin >> q;
    
    for(int i= 0; i < q; i++) {
        char c;
        cin >> c;
        if(c == 'U') {
            int idx, new_value;
            cin >> idx >> new_value;
            idx--;
            
            update(0, n - 1, 1, idx, new_value);
        }
        else {
            int a, b;
            cin >> a >> b;
            a--; b--;
            
            pair p = query(0, n - 1, 1, a, b);
            cout << p.first + p.second << endl;
        }
    }
    return 0;
}