#include <bits/stdc++.h>
using namespace std;
int n, m;
const int N = 2e5 + 10;
int w[N];
typedef long long LL;
struct node {
int l, r;
LL lazy, sum;
};
node tr[N * 4];
void pushup(int u) {
tr[u].sum = tr[u << 1].sum + tr[u << 1 | 1].sum;
}
void cal(int u, int lazy, int l, int r) {
if (lazy == 0)
return;
tr[u].lazy = (tr[u].l - l + lazy);
//先赋值后计算
if ((tr[u].r - tr[u].l + 1) % 2 == 0) {
tr[u].sum = (tr[u].r - tr[u].l + 1) / 2 * (LL)(tr[u].lazy + tr[u].lazy + r - l) ;
} else {
tr[u].sum = (LL)(tr[u].lazy + tr[u].lazy + r - l) / 2 * (LL)(tr[u].r - tr[u].l + 1);
}
}
void pushdown(int u) {
if (tr[u].lazy == 0)
return;
cal(u << 1, tr[u].lazy, tr[u].l, tr[u].r), cal(u << 1 | 1, tr[u].lazy, tr[u].l, tr[u].r);
tr[u].lazy = 0;
}
void build(int u, int l, int r) {
if (l == r) {
tr[u] = {l, r, 0, w[r]};
} else {
tr[u] = {l, r};
int mid = tr[u].l + tr[u].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) {
cal(u, d, l, r);
} else {
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;
} else {
pushdown(u);
int mid = tr[u].l + tr[u].r >> 1;
LL res = 0;
if (l <= mid )
res += query(u << 1, l, r);
if (r > mid)
res += query(u << 1 | 1, l, r);
return res;
}
}
int main() {
cin >> n >> m;
for (int i = 1; i <= n; i++)
scanf("%d", &w[i]);
build(1, 1, n);
while (m--) {
int op, l, r, d;
scanf("%d%d%d", &op, &l, &r);
if (op == 2) {
cout << query(1, l, r) << endl;
} else {
scanf("%d", &d);
modify(1, l, r, d);
}
}
}