线段树模板（区间更新，区间求和，区间最值）

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线段树模板

#include <iostream>
#include <stdio.h>
#define ll long long
#define lson l, mid, rt << 1
#define rson mid + 1, r, rt << 1 | 1
#define il inline
using namespace std;
const ll MAXN = 1e5 + 10;
struct Tree {//定义结构
	ll sum;
	ll lazy;
	ll maxn;
	ll minn;
} t[MAXN<<2];
il void push_up(ll rt) { //向上更新
	t[rt].sum = t[rt << 1].sum + t[rt << 1 | 1].sum;
	t[rt].maxn = max(t[rt << 1].maxn ,t[rt << 1 | 1].maxn);
	t[rt].minn = min(t[rt << 1].minn ,t[rt << 1 | 1].minn);
}
il void push_down(ll rt, ll m) {//pushdown函数
	if(t[rt].lazy) { //若有标记,则将标记向下移动一层
		t[rt << 1].lazy += t[rt].lazy;
		t[rt << 1 | 1].lazy += t[rt].lazy;
		t[rt << 1].sum += (m - (m >> 1)) * t[rt].lazy;
		t[rt << 1 | 1].sum += (m >> 1) * t[rt].lazy;
		t[rt << 1].minn += t[rt].lazy;
		t[rt << 1 | 1].minn+= t[rt].lazy;
		t[rt << 1].maxn += t[rt].lazy;
		t[rt << 1 | 1].maxn+= t[rt].lazy;
		t[rt].lazy = 0;//取消本层标记
	}
}
il void build(ll l,ll r, ll rt) { //建树
	t[rt].lazy = 0;
	if(l == r) {
		scanf("%lld",&t[rt].sum);
		t[rt].minn=t[rt].sum;
		t[rt].maxn=t[rt].sum;
		return;
	}
	ll mid = (l + r) >> 1;
	build(lson);
	build(rson);
	push_up(rt);//向上更新
}
il void update(ll L,ll R, ll key, ll l,ll r, ll rt) { //区间更新
	if(L <= l && R >= r) {
		t[rt].sum+=(r - l + 1) * key;
		t[rt].minn+=key;
		t[rt].maxn+=key;
		t[rt].lazy+=key;
		return;
	}
	push_down(rt, r - l + 1);//向下更新
	long long int mid = (l + r) >> 1;
	if(L <= mid) update(L, R, key, lson);
	if(R > mid) update(L, R, key, rson);
	push_up(rt);//向上更新
}
il ll query(ll L, ll R, ll l, ll r,ll rt) { //区间求和
	if(L <= l && R >= r) return t[rt].sum;
	push_down(rt, r - l + 1);//向下更新
	ll mid = (l + r) >> 1;
	ll ans = 0;
	if(L <= mid) ans += query(L, R, lson);
	if(R > mid) ans += query(L, R, rson);
	return ans;
}
il ll query_min(ll L, ll R, ll l, ll r,ll rt) { //区间求最小值
	if(L <= l && R >= r) return t[rt].minn;
	push_down(rt, r - l + 1);//向下更新
	ll mid = (l + r) >> 1;
	ll ans = 0x3f3f3f3f;
	if(L <= mid) ans = min(ans,query_min(L, R, lson));
	if(R > mid) ans =min(ans,query_min(L, R, rson)) ;
	return ans;
}
il ll query_max(ll L, ll R, ll l, ll r,ll rt) { //区间求最大值
	if(L <= l && R >= r) return t[rt].maxn;
	push_down(rt, r - l + 1);//向下更新
	ll mid = (l + r) >> 1;
	ll ans = 0;
	if(L <= mid) ans = max(ans,query_max(L, R, lson));
	if(R > mid) ans = max(ans,query_max(L, R, rson));
	return ans;
}
int main() {
	ll n,l,r,v;
	char a;
	int t;
	cin>>t;
	for(ll i=1; i<=t; i++) {
		scanf("%lld", &n);
		build(1, n, 1);
		while(cin>>a&&a!='e') {
			if(a=='a') {
				scanf("%lld%lld%lld",&l,&r,&v);
				update(l,r,v,1,n,1);
			} else if(a=='s') {
				scanf("%lld%lld",&l,&r);
				printf("%lld\n",query(l,r,1,n,1));
			} else if(a=='m') {
				scanf("%lld%lld",&l,&r);
				printf("%lld\n",query_min(l,r,1,n,1));
			} else {
				scanf("%lld%lld",&l,&r);
				printf("%lld\n",query_max(l,r,1,n,1));
			}
		}
	}
	return 0;
}