#include<iostream>

using namespace std;
const int N = 1e5 + 10;
int n, m, a[N];
typedef long long LL;
LL tr1[N], tr2[N];

int lowbit(int x) {
    return x & -x;
}

void add(LL tr[], int x, LL c) {
    for (int i = x; i <= n; i += lowbit(i)) tr[i] += c;
}

LL sum(LL tr[], int x) {
    LL res = 0;
    for (int i = x; i; i -= lowbit(i)) res += tr[i];
    return res;
}

LL psum(int x) {
    return sum(tr1, x) * (x + 1) - sum(tr2, x);
}

int main() {
    cin >> n >> m;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        int b = a[i] - a[i - 1];
        add(tr1, i, b);
        add(tr2, i, (LL) b * i);
    }

    while (m--) {
        char op;
        LL l, r, d;
        cin >> op >> l >> r;
        if (op == 'Q') {
            cout << psum(r) - psum(l - 1) << endl;
        } else {
            cin >> d;
            add(tr1, l, d), add(tr2, l, l * d);
            add(tr1, r + 1, -d), add(tr2, r + 1, -(r + 1) * d);
        }
    }
}