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#pragma GCC optimize(2)
#include <cstdio>
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <string>
#include <cstring>
#include <algorithm>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <ctime>
#include <vector>
#include <fstream>
#include <list>
#include <iomanip>
#include <numeric>
using namespace std;
typedef long long ll;

const int MAXN = 1e6 + 10;


ll arr[MAXN] = {0};

ll tree[MAXN * 4 + 10] = {0};

ll b[MAXN] = {0};

void init(int now, int l, int r)
{
	if(l == r)
	{
		tree[now] = arr[l];
		return ;
	}
	
	int mid = l + (r - l) / 2;
	
	init(now * 2, l, mid);
	
	init(now * 2 + 1, mid + 1, r);
	
	tree[now] = tree[now * 2] + tree[now * 2 + 1];
}

void pushdown(int now, int l , int r)
{
	if(b[now])
	{
		b[now * 2] += b[now];
		
		b[now * 2 + 1] += b[now];
		
		int mid = l + (r - l) / 2;
		
		tree[now * 2] += b[now] * (mid - l + 1);
		
		tree[now * 2 + 1] += b[now] * (r - mid);
		
		b[now] = 0; 
	}
}

ll find(int now, int l, int r, int x, int y)
{
	if(x > r || y < l)
		return 0;
		
	if(x <= l && y >= r)
	{	
		return tree[now]; 
	}
	
	pushdown(now, l, r);
	
	int mid = l + (r - l) / 2;
	
	ll ans = 0;
	
	ans += find(now * 2, l, mid, x, y);
	
	ans += find(now * 2 + 1, mid + 1, r, x, y);
	
	return ans;
}



void update(int now, int l, int r, int x, int y, ll add)
{	
	if(l > y || x > r) 
		return ;
		
	if(l >= x && r <= y) 
	{
		b[now] += add;
		
		tree[now] += add * (r - l + 1);
		
		return ;
	}
	
	pushdown(now, l, r);
	
	int mid = l + (r - l) / 2;	
	
	update(now * 2, l, mid, x, y, add);
	
	update(now * 2 + 1, mid + 1, r, x , y, add);
	
	tree[now] = tree[now * 2] + tree[now * 2 + 1];
	
}

int main()
{
	ios::sync_with_stdio(false);

	cin.tie(0);

	cout.tie(0);

    ll len, oprt;

    cin>>len>>oprt;

    for(int i = 1; i <= len; i++)
        cin>>arr[i];

    init(1, 1, len);
	
	int x, y;

	while(oprt--)
	{
		int mode, x, y, k;
		
		cin>>mode;
		
		if(mode == 1)
		{
			cin>>x>>y>>k;
			
			update(1, 1, len, x, y, k);
		}
		else
		{
			cin>>x>>y;
			
			cout<<find(1, 1, len, x, y)<<endl;
		}
		
	}

    return 0;
}