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struct Segment_Tree {
    #define ls (p << 1)
    #define rs (p << 1 | 1)
    #define mid ((l + r) >> 1)
    ll ans[_ << 2], tag[_ << 2];
    inline void pushup(ll p) { ans[p] = ans[ls] + ans[rs]; }
    inline void pushdown(ll p, ll l, ll r) {
        ans[ls] += (mid - l + 1) * tag[p];
        tag[ls] += tag[p];
        ans[rs] += (r - mid) * tag[p];
        tag[rs] += tag[p];
        tag[p] = 0;
    }
    void build(ll p, ll l, ll r) {
        if(l == r) {
            ans[p] = a[l];
            return;
        }
        build(ls, l, mid);
        build(rs, mid + 1, r);
        pushup(p);
    }
    void update(ll p, ll l, ll r, ll ul, ll ur, ll k) {
        if(ul <= l && r <= ur) {
            ans[p] += (r - l + 1) * k;
            tag[p] += k;
            return;
        }
        if(tag[p]) pushdown(p, l, r);
        if(ul <= mid) update(ls, l, mid, ul, ur, k);
        if(ur > mid) update(rs, mid + 1, r, ul, ur, k);
        pushup(p);
    }
    ll query(ll p, ll l, ll r, ll ql, ll qr) {
        if(ql <= l && r <= qr) return ans[p];
        if(tag[p]) pushdown(p, l, r);
        ll res = 0;
        if(ql <= mid) res += query(ls, l, mid, ql, qr);
        if(qr > mid) res += query(rs, mid + 1, r, ql, qr);
        return res;
    }
    #undef ls
    #undef rs
    #undef mid
}T;