线段树区间更新的模板题，重写了一下，发现太手生了。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;typedef long long ll;
const int N = 100005;
int a[N],n,m;struct node
{int l,r;ll sum,lazy;
}tree[N<<4];void push_up(int rt)
{tree[rt].sum = tree[rt<<1].sum + tree[rt<<1|1].sum;
}
void push_down(int rt,int m)
{if(tree[rt].lazy){tree[rt<<1].lazy += tree[rt].lazy;tree[rt<<1|1].lazy += tree[rt].lazy;tree[rt<<1].sum += tree[rt].lazy * (m-(m>>1));tree[rt<<1|1].sum += tree[rt].lazy * (m>>1);tree[rt].lazy = 0;}
}
void build(int l,int r,int rt)
{tree[rt].l = l;tree[rt].r = r;tree[rt].sum = tree[rt].lazy = 0;if(l == r)tree[rt].sum = a[l];else{int mid = (l+r)>>1;build(l,mid,rt<<1);build(mid+1,r,rt<<1|1);push_up(rt);}
}void update(int val,int l,int r,int rt)
{if(tree[rt].l == l && tree[rt].r == r){tree[rt].lazy += 1ll*val;tree[rt].sum += 1ll*val*(r-l+1);return;}if(tree[rt].l == tree[rt].r)return;push_down(rt,tree[rt].r-tree[rt].l+1);int mid = (tree[rt].l+tree[rt].r)>>1;if(r <= mid)update(val,l,r,rt<<1);else if(l > mid)update(val,l,r,rt<<1|1);else{update(val,l,mid,rt<<1);update(val,mid+1,r,rt<<1|1);}push_up(rt);
}
ll query(int l,int r,int rt)
{if(tree[rt].l == l && tree[rt].r == r)return tree[rt].sum;push_down(rt,tree[rt].r-tree[rt].l+1);int mid = (tree[rt].l+tree[rt].r)>>1;ll ans = 0;if(r <= mid)ans += query(l,r,rt<<1);else if(l > mid)ans += query(l,r,rt<<1|1);else{ans += query(l,mid,rt<<1);ans += query(mid+1,r,rt<<1|1);}//printf("dsjilsdfgsd f\n");return ans;
}
int main()
{scanf("%d",&n);for(int i = 1;i <= n;i++)scanf("%d",&a[i]);build(1,n,1);scanf("%d",&m);while(m--){int l,r,val;scanf("%d%d%d",&l,&r,&val);update(val,l,r,1);//printf("dsjils\n");printf("%lld\n",query(l,r,1));}return 0;
}