区区区间

#include<iostream>
#include<algorithm>
using namespace std;
#define lson o << 1, l, M
#define rson o << 1 | 1, M+1, r
#define lo o << 1
#define ro o << 1 | 1
const int N = 2e5 + 10;
long long v[N << 2], lazy[N << 2];
inline void pushup(int o) {
    v[o] = v[o << 1] + v[o << 1 | 1];
}
inline long long cal(long long a0, long long n) {
    return a0 * n + (n - 1) * n / 2;
}
inline void pushdown(int o, int ln, int rn) {
    if(lazy[o]) {
        lazy[lo] = lazy[o];
        lazy[ro] = lazy[o] + ln;
        v[lo] = cal(lazy[o], ln);
        v[ro] = cal(lazy[ro], rn);
        lazy[o] = 0;
    }
}
void Build(int o, int l, int r) {
    if(l == r) {
        scanf("%lld", &v[o]);
        return ;
    }
    int M = (l + r) / 2;
    Build(lson);
    Build(rson);
    pushup(o);
}
void update(int L, int R, long long k, int o, int l, int r) {
    if(L <= l) {
        if(R >= r) {
            long long C = k + (l - L);
            v[o] = cal(C, r - l + 1);
            lazy[o] = C;
            return ;
        }
    }
    int M = (l + r) / 2;
    pushdown(o, M - l + 1, r - M);
    if(L <= M)
        update(L, R, k, lson);
    if(R > M)
        update(L, R, k, rson);
    pushup(o);
}
long long query(int L, int R, int o, int l, int r) {
    if(L <= l) {
        if(R >= r)
            return v[o];
    }
    int M = (l + r) / 2;
    pushdown(o, M - l + 1, r - M);
    long long Sum = 0;
    if(L <= M)
        Sum += query(L, R, lson);
    if(R > M)
        Sum += query(L, R, rson);
    return Sum;
}
int main() {
    int n, m;
    scanf("%d%d", &n, &m);
    Build(1, 1, n);
    int op, l, r;
    long long k;
    while(m--) {
        scanf("%d%d%d", &op, &l, &r);
        if(op == 1) {
            scanf("%lld", &k);
            update(l, r, k, 1, 1, n);
        } else
            printf("%lld\n", query(l, r, 1, 1, n));
    }
    return 0;
}