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#include <iostream>
#include <cstring>
#include <algorithm>

using namespace std;
int n, m;
const int N = 1e5+5;
typedef long long LL;

int w[N];
struct Node{
    
    
    int l, r;
    LL sum, add;
}tr[4*N];

void pushup(int u){
    
    
    tr[u].sum = tr[u<<1].sum + tr[u<<1|1].sum;
}

void pushdown(int u){
    
    
    auto &root = tr[u], &left = tr[u<<1], &right = tr[u<<1|1];
    if(root.add){
    
    
        left.add += root.add; left.sum += (LL)(left.r - left.l + 1)*root.add;
        right.add += root.add; right.sum += (LL)(right.r - right.l + 1)*root.add;
        root.add = 0; //这里一定要清空
    }
}
void build(int u, int l, int r)
{
    
    
    if (l == r) tr[u] = {
    
    l, r, w[r], 0}; //bug出在这里 把w[r]写成了w[u]着实难发现
    else
    {
    
    
        tr[u] = {
    
    l, r};
        int mid = l + r >> 1;
        build(u << 1, l, mid), build(u << 1 | 1, mid + 1, r);
        pushup(u);
    }
}

void modify(int u, int l, int r, int d)
{
    
    
    if (tr[u].l >= l && tr[u].r <= r)
    {
    
    
        tr[u].sum += (LL)(tr[u].r - tr[u].l + 1) * d;
        tr[u].add += d;
    }
    else    // 一定要分裂
    {
    
    
        pushdown(u);
        int mid = tr[u].l + tr[u].r >> 1;
        if (l <= mid) modify(u << 1, l, r, d);
        if (r > mid) modify(u << 1 | 1, l, r, d);
        pushup(u);
    }
}




LL query(int u, int l, int r)
{
    
    
    if (tr[u].l >= l && tr[u].r <= r) return tr[u].sum;

    pushdown(u);
    int mid = tr[u].l + tr[u].r >> 1;
    LL sum = 0;
    if (l <= mid) sum = query(u << 1, l, r);
    if (r > mid) sum += query(u << 1 | 1, l, r);
    return sum;
}
int main()
{
    
    
    scanf("%d%d", &n, &m);

    for (int i = 1; i <= n; i ++ ) scanf("%d", &w[i]);

    build(1, 1, n);

    char op[2];
    int l, r, d;

    while (m -- )
    {
    
    
        scanf("%s%d%d", op, &l, &r);
        if (*op == 'C')
        {
    
    
            scanf("%d", &d);
            modify(1, l, r, d);
        }
        else printf("%lld\n", query(1, l, r));
    }

    return 0;
}