//sum:区间加和
//add懒标记：父亲+自己已加，孩子要加未加，父亲裂开时要加。
//使用add, add = 0, 子++，子标记。
//接收add: 自add+=add(继承标记！！！)

#include<bits/stdc++.h>
using namespace std;
const int N = 1e5 + 5;
typedef long long L;
int n,m,d;
int x,y;
L w[N];
struct A {
    int l,r;
    L 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) {
    if(tr[u].add) {
        tr[u<<1].add += tr[u].add;
        tr[u<<1|1].add += tr[u].add;
        tr[u<<1].sum += (tr[u<<1].r - tr[u<<1].l+1)*tr[u].add;
        tr[u<<1|1].sum += (tr[u<<1|1].r - tr[u<<1|1].l+1)*tr[u].add;
        tr[u].add = 0;
    }
}
void build(int u,int l,int r) {
    if(l==r) {
        tr[u] = {l,l,w[l],0};
    }
    else {
        tr[u] = {l,r};
        int m = l + r >> 1;
        build(u<<1,l,m);build(u<<1|1,m+1,r);
        pushup(u);
    }
}
L query(int u,int l,int r) {
    if(tr[u].l >= l && tr[u].r<=r) {
        return tr[u].sum;
    }
    else {
        int m = tr[u].l + tr[u].r >> 1;
        pushdown(u);
        L s = 0;
        if(l<=m) s = query(u<<1,l,r);
        if(m<r) s+=query(u<<1|1,l,r);
        pushup(u);
        return s;
    }
}
void modity(int u,int l,int r, L c) {
    if(tr[u].l>=l&&tr[u].r<=r) {
        tr[u].sum += (tr[u].r - tr[u].l + 1)*c;
        tr[u].add+=c;
    }
    else {
        int m = tr[u].r + tr[u].l>>1;
        pushdown(u);
        if(l<=m) modity(u<<1,l,r,c);
        if(m<r) modity(u<<1|1,l,r,c);
        pushup(u);
    }
}

int main() {
    cin>>n>>m;
    for(int i = 1; i <= n; ++i) cin>>w[i];
    build(1,1,n);
    while(m--) {
        char c;
        cin>>c;
        if(c=='C') {
            cin>>x>>y>>d;
            modity(1,x,y,d);
        }
        else {
            cin>>x>>y;
            cout<<query(1,x,y)<<endl;
        }
    }
}