#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cmath>
#include <set>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
const int mod = 1000000007;

int main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int n, k, m, q, u, v, c[3][1000006] = {};
    set<int> s[3] = {};
    cin >> n >> k >> m >> q;
    for (int i = 1; i < k; i++) cin >> c[0][i];
    for (int i = k; i <= n; i++) cin >> c[1][i];
    for (int i = 0; i <= m; i++) cin >> c[2][i];
    for (int i = 1; i < k; i++) c[0][i] += c[0][i - 1];
    for (int i = k; i <= n; i++) c[1][i] += c[1][i - 1];
    for (int i = 1; i <= m; i++) c[2][i] += c[2][i - 1];
    while (q--) {
        char o;
        cin >> o;
        if (o == 'c') {
            cin >> u;
            if (u < k) {
                if (s[0].find(u) == s[0].end()) s[0].insert(u);
                else s[0].erase(u);
            } else {
                if (s[1].find(u) == s[1].end()) s[1].insert(u);
                else s[1].erase(u);
            }
        } else if (o == 'x') {
            cin >> u;
            if (s[2].find(u) == s[2].end()) s[2].insert(u);
            else s[2].erase(u);
        } else {
            int z = mod;
            cin >> u >> v;
            if (u > v) swap(u, v);
            int x = 0, y = 0;
            if (u < k) x = 0;
            else if (u <= n) x = 1;
            else x = 2;
            if (v < k) y = 0;
            else if (y <= n) y = 1;
            else y = 2;
            int d[7] = {};
            for (int i = 0; i < 7; i++) d[i] = 5e8;
            if (s[0].empty()) d[0] = c[0][k - 1];
            if (s[1].empty()) d[1] = c[1][n];
            if (s[2].empty()) d[2] = c[2][m];
            if (x == 0) {
                if (s[0].empty() || *s[0].begin() >= u) d[3] = c[0][u - 1];
                if (s[0].empty() || *s[0].rbegin() < u) d[4] = c[0][k - 1] - c[0][u - 1];
            } else if (x == 1) {
                if (s[1].empty() || *s[1].rbegin() < u) d[3] = c[1][n] - c[1][u - 1];
                if (s[1].empty() || *s[1].begin() >= u) d[4] = c[1][u - 1];
            } else {
                if (s[2].empty() || *s[2].begin() >= u - n) d[3] = c[2][u - n - 1];
                if (s[2].empty() || *s[2].rbegin() < u - n) d[4] = c[2][m] - c[2][u - n - 1];
            }
            if (y == 0) {
                if (s[0].empty() || *s[0].begin() >= v) d[5] = c[0][v - 1];
                if (s[0].empty() || *s[0].rbegin() < v) d[6] = c[0][k - 1] - c[0][v - 1];
            } else if (y == 1) {
                if (s[1].empty() || *s[1].rbegin() < v) d[5] = c[1][n] - c[1][v - 1];
                if (s[1].empty() || *s[1].begin() >= v) d[6] = c[1][v - 1];
            } else {
                if (s[2].empty() || *s[2].begin() >= v - n) d[5] = c[2][v - n - 1];
                if (s[2].empty() || *s[2].rbegin() < v - n) d[6] = c[2][m] - c[2][v - n - 1];
            }
            //for (int i = 0; i < 7; i++) cout << d[i] << ' ';
            if (x == y) {
                if (x == 0) {
                    if (s[0].empty() || *s[0].lower_bound(u) >= v) z = min(z, c[0][v - 1] - c[0][u]);
                } else if (x == 1) {
                    if (s[1].empty() || *s[1].lower_bound(u) >= v) z = min(z, c[1][v - 1] - c[0][u]);
                } else {
                    if (s[2].empty() || *s[2].lower_bound(u - n) >= v - n) z = min(z, c[2][v - n - 1] - c[2][u - n - 1]);
                }
            }
            z = min(z, d[3] + d[5]);
            z = min(z, d[4] + d[6]);
            z = min(z, d[3] + min({d[0], d[1], d[2]}) + d[6]);
            z = min(z, d[4] + min({d[0], d[1], d[2]}) + d[5]);
            if (z > 4e8) cout << "impossible\n";
            else cout << z << '\n';
        }
    }
}