本蒟蒻刚学线段树，求各位神犇优化一下

#include <bits/stdc++.h>
using namespace std;
#define ll unsigned long long

ll tree[300000], k[100001], n, m;

ll read()
{
	char c=getchar();ll s=0;int f=1;
	while(c<'0'||c>'9')
	{
		if(c=='-') f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9')
	{
		s=s*10+c-'0';
		c=getchar();
	}
	return s*f;
}

void build(int l, int r, int p=1)
{
	if(l==r)
	{
		tree[p]=k[l];
		return;
	}
	int mid=(l+r)/2;
	build(l, mid, p*2);
	build(mid+1, r, p*2+1);
	tree[p]=tree[p*2]+tree[p*2+1];
}

void add(int l, int r, int nl, int nr, int num, int p=1)
{
	if(l==r&&l>=nl&&r<=nr)
	{
		tree[p]+=num;
		k[l]+=num;
		return;
	}
	if(l==r) return;
	int mid=(l+r)/2;
	add(l, mid, nl, nr, num, p*2);
	add(mid+1, r, nl, nr, num, p*2+1);
	tree[p]=tree[p*2]+tree[p*2+1];
}

ll query(int l, int r, int nl, int nr, int p=1)
{
	if(l>=nl&&r<=nr) return tree[p];
	if((l<nl&&r<nl)||(r>nr&&l>nr)) return 0;
	int mid=(l+r)/2;ll sum=0;
	sum+=query(l, mid, nl, nr, p*2);
	sum+=query(mid+1, r, nl, nr, p*2+1);
	return sum;
}

int main()
{
	n=read(), m=read();
	int a, b, c, d;
	for(int i=1;i<=n;i++)
	{
		k[i]=read();
	}build(1, n);
	for(int i=1;i<=m;i++)
	{
		a=read();
		if(a==1)
		{
			b=read(), c=read(), d=read();
			add(1, n, b, c, d);
		}
		else if(a==2)
		{
			b=read(), c=read();
			cout<<query(1, n, b, c)<<endl;
		}
	}
	return 0;
}