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题意:传送门
原题目描述在最下面。
4种操作,1:区间加法,2:区间乘法,3:区间的所有数都变成一个数,4:访问区间每个数的p次方和(1 <= p <= 3)。
思路:
三个lazy标记:lazy1表示区间加上的数的延迟,lazy2表示区间乘上的数的延迟,lazy3表示区间变成的那个数字。初始化lazy1 = lazy3 = 0, lazy2 = 1
.
如果进行3号操作,则将lazy1和lazy2全部恢复初始值。
对于1,2号操作,假设原数是x,乘上a,加上b。则 \(a \Rightarrow a \times x + b\) 。
$$sum1 = \sum x \Rightarrow \sum (a\times x + b) = sum1 \times a + b \times length$$
$$sum2 = \sum x^2 \Rightarrow \sum (a\times x + b)^2 \Rightarrow \sum (a^2\times x2+2\times a\times b\times x)=sum2\times a2 \times length+2\times a\times b\times sum1
\]
注意了,再进行更新sum操作时,要先更新sum3再更新sum2最后更新sum1。比如sum3式子中的sum2的含义是原始数列的sum2,不是更新后的sum2。
然后就是对于push_down中的lazy1和lazy2的处理。
\(lazy1 \Rightarrow lazy1\times a + b\)
$lazy2 \Rightarrow lazy2\times a $
(因为update哪里忘了写return;
,导致debug一天)
AC代码:
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <set>
#include<assert.h>
#define lson rt<<1
#define rson rt<<1|1
#define lowbit(x) (x)&(-(x))
using namespace std;
typedef long long LL;
const int INF = 0x3f3f3f3f;
const int N = (int)1e5+7;
const int mod = 10007;
int n, q;
int ar[N];
struct lp{
int l,r;
LL sum1,sum2,sum3,d;
LL lazy1,lazy2,lazy3;
}cw[N<<2];
//pushdown先乘除后加减
//加法 lazy1 lazy2 乘法
void push_up(int rt){
cw[rt].sum1 = (cw[lson].sum1+cw[rson].sum1)%mod;
cw[rt].sum2 = (cw[lson].sum2+cw[rson].sum2)%mod;
cw[rt].sum3 = (cw[lson].sum3+cw[rson].sum3)%mod;
}
void build(int l,int r,int rt){
int m=(l+r)>>1;
cw[rt].l=l;cw[rt].r=r;
cw[rt].d=r-l+1;
cw[rt].sum1 = cw[rt].sum2 = cw[rt].sum3=0;
cw[rt].lazy1 = cw[rt].lazy3 = 0;
cw[rt].lazy2 = 1;
if(l==r){return;}
build(l,m,lson); build(m+1,r,rson);
push_up(rt);
}
//pushdown先乘除后加减
void push_down(int rt){
if(cw[rt].lazy3){
LL tmp = cw[rt].lazy3*cw[rt].lazy3%mod*cw[rt].lazy3%mod;
cw[lson].lazy1=cw[rson].lazy1=0;
cw[lson].lazy2=cw[rson].lazy2=1;
cw[lson].lazy3=cw[rson].lazy3=cw[rt].lazy3;
cw[lson].sum3 = cw[lson].d*tmp%mod;
cw[rson].sum3 = cw[rson].d*tmp%mod;
cw[lson].sum2 = cw[lson].d*cw[rt].lazy3%mod*cw[rt].lazy3%mod;
cw[rson].sum2 = cw[rson].d*cw[rt].lazy3%mod*cw[rt].lazy3%mod;
cw[lson].sum1 = cw[lson].d*cw[rt].lazy3%mod;
cw[rson].sum1 = cw[rson].d*cw[rt].lazy3%mod;
cw[rt].lazy3 = 0;
}
if(cw[rt].lazy1!=0||cw[rt].lazy2!=1){
LL add = cw[rt].lazy1, mul = cw[rt].lazy2;
LL l1=cw[lson].sum1,l2=cw[lson].sum2,l3=cw[lson].sum3;
LL r1=cw[rson].sum1,r2=cw[rson].sum2,r3=cw[rson].sum3;
LL tmp = mul*mul%mod*mul%mod;
cw[lson].lazy1=(cw[lson].lazy1*mul%mod+add)%mod;
cw[rson].lazy1=(cw[rson].lazy1*mul%mod+add)%mod;
cw[lson].lazy2=cw[lson].lazy2*mul%mod;
cw[rson].lazy2=cw[rson].lazy2*mul%mod;
cw[lson].sum3=(cw[lson].sum3*tmp%mod + add*add%mod*add%mod*cw[lson].d%mod + 3*cw[lson].sum2*mul%mod*mul%mod*add%mod + 3*cw[lson].sum1*mul%mod*add%mod*add%mod)%mod;
cw[rson].sum3=(cw[rson].sum3*tmp%mod + add*add%mod*add%mod*cw[rson].d%mod + 3*cw[rson].sum2*mul%mod*mul%mod*add%mod + 3*cw[rson].sum1*mul%mod*add%mod*add%mod)%mod;
cw[lson].sum2=(cw[lson].sum2*mul%mod*mul%mod + add*add%mod*cw[lson].d%mod + 2*mul*add*cw[lson].sum1)%mod;
cw[rson].sum2=(cw[rson].sum2*mul%mod*mul%mod + add*add%mod*cw[rson].d%mod + 2*mul*add*cw[rson].sum1)%mod;
cw[lson].sum1=(cw[lson].sum1*mul+add*cw[lson].d)%mod;
cw[rson].sum1=(cw[rson].sum1*mul+add*cw[rson].d)%mod;
cw[rt].lazy1 = 0;cw[rt].lazy2 = 1;
}
}
//op==1 加法, op==2 乘法, op==3 改变值
void update(int L,int R,int op,int z,int rt){
int l=cw[rt].l, r=cw[rt].r, mid=(l+r)>>1;
if(cw[rt].l>R||cw[rt].r<L)return;
if(L<=l&&r<=R){
LL l1 = cw[rt].sum1, l2 = cw[rt].sum2;
if(op==1){//加法
cw[rt].lazy1 = (z + cw[rt].lazy1)%mod;
cw[rt].sum3 = (cw[rt].sum3 + (z*z%mod)*z%mod*cw[rt].d%mod + 3*z*(cw[rt].sum2+(cw[rt].sum1*z)%mod)%mod)%mod;
cw[rt].sum2 = (cw[rt].sum2 + cw[rt].d*z%mod*z%mod + 2*z*cw[rt].sum1%mod)%mod;
cw[rt].sum1 = (cw[rt].sum1 + cw[rt].d*z%mod)%mod;
}else if(op==2){//乘法
cw[rt].lazy1 = cw[rt].lazy1*z%mod;
cw[rt].lazy2 = cw[rt].lazy2*z%mod;
cw[rt].sum1 = cw[rt].sum1*z%mod;
cw[rt].sum2 = (cw[rt].sum2*z%mod)*z%mod;
cw[rt].sum3 = ((cw[rt].sum3*z%mod)*z%mod)*z%mod;
}else{
cw[rt].lazy1=0;cw[rt].lazy2=1;
cw[rt].lazy3=z;
cw[rt].sum3 = cw[rt].d*z%mod*z%mod*z%mod;
cw[rt].sum2 = cw[rt].d*z%mod*z%mod;
cw[rt].sum1 = cw[rt].d*z%mod;
}
return;
}
if(cw[rt].l==cw[rt].r)return;
push_down(rt);
if(L>mid)update(L,R,op,z,rson);
else if(R<=mid)update(L,R,op,z,lson);
else{
update(L,mid,op,z,lson);
update(mid+1,R,op,z,rson);
}
push_up(rt);
}
LL query(int L,int R,int op,int rt){
int l=cw[rt].l, r=cw[rt].r, mid=(l+r)>>1;
if(L<=l&&r<=R){
if(op==1)return cw[rt].sum1;
else if(op==2)return cw[rt].sum2;
return cw[rt].sum3;
}
if(cw[rt].l==cw[rt].r)return 0;
push_down(rt);
LL sum = 0;
if(L>mid) sum = query(L,R,op,rson);
else if(R<=mid) sum = query(L,R,op,lson);
else {
sum = query(L,mid,op,lson);
sum += query(mid+1,R,op,rson);
}
return (sum%mod);
}
int main(){
while(~scanf("%d%d", &n,&q)&&(n+q)){
build(1,n,1);
while(q--){
int op,l,r,z;
scanf("%d%d%d%d",&op,&l,&r,&z);
if(op<=3){
z%=mod;
update(l,r,op,z,1);
}else{
printf("%lld\n", query(l,r,z,1));
}
}
}
return 0;
}
####原题目描述:
Problem Description
Yuanfang is puzzled with the question below:
There are n integers, a1, a2, …, an. The initial values of them are 0. There are four kinds of operations.
Operation 1: Add c to each number between ax and ay inclusive. In other words, do transformation akInput
There are no more than 10 test cases.
For each case, the first line contains two numbers n and m, meaning that there are n integers and m operations. 1 <= n, m <= 100,000.
Each the following m lines contains an operation. Operation 1 to 3 is in this format: "1 x y c" or "2 x y c" or "3 x y c". Operation 4 is in this format: "4 x y p". (1 <= x <= y <= n, 1 <= c <= 10,000, 1 <= p <= 3)
The input ends with 0 0.
Output
For each operation 4, output a single integer in one line representing the result. The answer may be quite large. You just need to calculate the remainder of the answer when divided by 10007.
Sample Input
5 5
3 3 5 7
1 2 4 4
4 1 5 2
2 2 5 8
4 3 5 3
0 0
Sample Output
307
7489
Source
2013ACM-ICPC杭州赛区全国邀请赛