修改区间可以改对应l, r原数组的两个点，二者之间的点再慢慢下推修改
1 #include<iostream>
2 #include<algorithm>
3 #include<cmath>
4 #include<cstdio>
5 #include<cstring>
6 #include<string>
7 #define ll long long
8 using namespace std;
9
10 const int N = 2e5 + 10;
11
12 int n, q;
13 ll tag, x, y;
14 ll a[N];
15
16 struct node
17 {
18 ll sum;
19 int lazy;
20 }t[N << 2];
21
22 inline void push_up(int root)
23 {
24 t[root].sum = t[root << 1].sum + t[root << 1 | 1].sum;
25 }
26
27 inline void push_down(int root, int l, int r)//
28 {
29 t[root].sum = 1ll * (r - l + 1) * t[root].lazy;
30 a[l] = a[r] = t[root].lazy;
31 if(l < r){
32 t[root << 1].lazy = t[root << 1 | 1].lazy = t[root].lazy;
33 }
34 t[root].lazy = 0;
35 }
36
37 inline void build(int l, int r, int root)
38 {
39 if(l == r){
40 t[root].sum = a[l];
41 t[root].lazy = 0;
42 return ;
43 }
44 int mid = (l + r) >> 1;
45 build(l, mid, root << 1);
46 build(mid + 1, r, root << 1 | 1);
47 push_up(root);
48 }
49
50 inline void upd(int l, int r, int root, ll x, ll y)
51 {
52 if(t[root].lazy){
53 push_down(root, l, r);
54 }
55 if(l > x || a[r] >= y) return ;
56 //当前区间左端点位于x右侧或右端点的值大于等于y，则无需更新
57 if(a[l] <= y && r <= x){
58 t[root].lazy = y;
59 push_down(root, l, r);//此处必须下推，确保a[l],a[r]已经修改，中间的a[]等下推再慢慢改
60 return ;
61 }
62 int mid = (l + r) >> 1;
63 upd(l, mid, root << 1, x, y);
64 upd(mid + 1, r, root << 1 | 1, x, y);
65 push_up(root);
66 }
67
68 ll now;
69 inline ll query(int l, int r, int root, ll x)
70 {
71 if(t[root].lazy){
72 push_down(root, l, r);
73 }
74 if(r < x || a[r] > now) return 0;//
75 if(now >= t[root].sum && l >= x){
76 now -= t[root].sum;
77 return r - l + 1ll;
78 }
79 if(l == r) return 0;////
80 int mid = (l + r) >> 1;
81 ll res = query(l, mid, root << 1, x);
82 res += query(mid + 1, r, root << 1 | 1, x);
83 return res;
84 }
85
86 int main(){
87 scanf("%d%d",&n,&q);
88 for(int i = 1 ; i <= n ; i++){
89 scanf("%lld",&a[i]);
90 }
91
92 build(1, n, 1);
93 for(int i = 1 ; i <= q ; i++){
94 scanf("%lld%lld%lld",&tag,&x,&y);
95 if(tag == 1){
96 upd(1, n, 1, x, y);
97 }else{
98 now = y;
99 printf("%lld
", query(1, n, 1, x));
100 }
101 }
102
103 return 0;
104 }