#include<bits/stdc++.h>
using namespace std;

typedef long long ll;

const int N = 1e6 + 10;
int c[N], x[N], prefc[N], prefx[N];

int n, k, m, q;

bool bannedC[N], bannedK[N];
set<int> banC, banK;

bool checkC(int L, int R) {
    if (L > R) return !bannedC[n] && checkC(L, n) && checkC(1, R);
    if (L == R) return 1;
    if (banC.lower_bound(L) == banC.end()) return 1;
    return *banC.lower_bound(L) >= R;
}

int sumC(int L, int R) {
    if (L > R) return sumC(L, n) + c[n] + sumC(1, R);
    return prefc[R - 1] - prefc[L - 1];
}

bool checkK(int L, int R) {
    L -= n, R -= n;
    if (L == R) return 1;
    if (banK.lower_bound(L) == banK.end()) return 1;
    return *banK.lower_bound(L) >= R;
}

int sumK(int x, int y) {
    return prefx[y - n - 1] - prefx[x - n - 1];
}

int direct(int x, int y) {
    int ret = 1e9;
    if (x <= n && y <= n) {
        if (checkC(x, y)) ret = min(ret, sumC(x, y));
        if (checkC(y, x)) ret = min(ret, sumC(y, x));
    }
    else {
        if (x > y) swap(x, y);
        if (checkK(x, y)) ret = min(ret, sumK(x, y));
    }
    return ret;
}

int k1() {
    int ret = direct(1, k);
    if (!banK.size()) ret = min(ret, prefx[m]);
    return ret;
}

int d1(int x) {
    if (x <= n) return direct(1, x);
    if (bannedK[0] || !checkK(n + 1, x)) return 1e9;
    return prefx[x - n - 1];
}

int dk(int x) {
    if (x <= n) return direct(x, k);
    if (bannedK[m] || !checkK(x, n + m)) return 1e9;
    return prefx[m] - prefx[x - n - 1];
}

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    if (fopen("qoj_5669.inp", "r")) {
        freopen("qoj_5669.inp", "r", stdin);
        freopen("qoj_5669.out", "w", stdout);
    }

    #ifdef LOCAL_MACHINE 
        if (fopen("task.inp", "r")) {
            freopen("task.inp", "r", stdin);
            freopen("task.out", "w", stdout);
        }
    #endif

    cin >> n >> k >> m >> q;
    for (int i = 1; i <= n; ++i) {
        cin >> c[i];
        prefc[i] = prefc[i - 1] + c[i];
    }
    for (int i = 0; i <= m; ++i) {
        cin >> x[i];
        prefx[i] = (i ? prefx[i - 1] : 0) + x[i];
    }
    while (q--) {
        char type; cin >> type;
        if (type == 'q') {
            int x, y; cin >> x >> y;
            int res = 1e9;
            if (x > y) swap(x, y);

            if (!(x <= n && y > n)) res = min(res, direct(x, y));
            res = min(res, d1(x) + d1(y));
            res = min(res, dk(x) + dk(y));
            res = min(res, d1(x) + k1() + dk(y));
            res = min(res, dk(x) + k1() + d1(y));

            if (res == 1e9) cout << "impossible\n";
            else cout << res << "\n";
        }
        else if (type == 'c') {
            int x; cin >> x;
            if (bannedC[x]) banC.erase(x);
            else banC.insert(x);
            bannedC[x] ^= 1;
        }
        else {
            int x; cin >> x;
            if (bannedK[x]) banK.erase(x);
            else banK.insert(x);
            bannedK[x] ^= 1;
        }
    }
}