#include <bits/stdc++.h>
#define f first
#define s second
#define mp make_pair
#define pb push_back
#define lp(i,a,n) for(int i=(a);i<=(int)(n);++i)
#define lpd(i,a,n) for(int i=(a);i>=(int)(n);--i)
#define mem(a,b) memset(a,b,sizeof a)
#define all(v) v.begin(),v.end()
#define println(a) cout <<(a) <<endl
#define sz(x) ((int)(x).size())
#define readi(x) scanf("%d",&x)
#define read2i(x,y) scanf("%d%d",&x,&y)
#define read3i(x,y,z) scanf("%d%d%d",&x,&y,&z)
#define readll(x) scanf("%I64d",&x)
#define mod 1000000007
#define eps 1e-6
#define infi 1000000000
#define infll 1000000000000000000ll
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vll;
typedef set<int> si;
typedef map<int,int> mii;

const int N = 100002;
int n,q,a[N];
ll tree[N],prodTreeL[N],prodTreeR[N];

void update(int i, ll diff, ll tree[]){
  while (i < N){
    tree[i] += diff;
    i += i & -i;
  }
}

ll query(int i, ll tree[]){
  ll sum = 0;
  while(i > 0){
    sum += tree[i];
    i -= i & -i;
  }
  return sum;
}

int main(){
    read2i(n,q);
    lp(i,1,n){
        readi(a[i]);
        update(i, a[i], tree);
        update(i, 1ll*i*a[i], prodTreeL);
        update(i, 1ll*(n-i+1)*a[i], prodTreeR);
    }

    while(q--){
        int t,l,r,k;
        read3i(t,l,r);
        if(t == 1){
            readi(k);
            ll ans = query(r, prodTreeR) - query(max(l-1,r-k), prodTreeR) - (n-r) * (query(r, tree) - query(max(l-1,r-k), tree));
            if(l <= r-k) ans += (k+1) * (query(max(l-1,r-k), tree) - query(l-1, tree));
            if(l > 1) ans += query(l-1, prodTreeL) - query(l-k-1, prodTreeL) - max(0, l-k-1) * (query(l-1, tree) - query(l-k-1, tree));
            println(ans);
        }
        else{
            update(l, -a[l] + r, tree);
            update(l, -1ll*l*a[l] + 1ll*l*r, prodTreeL);
            update(l, -1ll*(n-l+1)*a[l] + 1ll*(n-l+1)*r, prodTreeR);
            a[l] = r;
        }
    }
}

/*
6 100
1 2 3 4 5 6
*/

//freopen("input.txt","r",stdin);
//freopen("output.txt","w",stdout);
//ios::sync_with_stdio(0);cin.tie(0);