CF444C. DZY Loves Colors[线段树 区间]

C. DZY Loves Colors
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

DZY loves colors, and he enjoys painting.

On a colorful day, DZY gets a colorful ribbon, which consists of n units (they are numbered from 1 to n from left to right). The color of the i-th unit of the ribbon is i at first. It is colorful enough, but we still consider that the colorfulness of each unit is 0 at first.

DZY loves painting, we know. He takes up a paintbrush with color x and uses it to draw a line on the ribbon. In such a case some contiguous units are painted. Imagine that the color of unit i currently is y. When it is painted by this paintbrush, the color of the unit becomes x, and the colorfulness of the unit increases by |x - y|.

DZY wants to perform m operations, each operation can be one of the following:

  1. Paint all the units with numbers between l and r (both inclusive) with color x.
  2. Ask the sum of colorfulness of the units between l and r (both inclusive).

Can you help DZY?

Input

The first line contains two space-separated integers n, m (1 ≤ n, m ≤ 105).

Each of the next m lines begins with a integer type (1 ≤ type ≤ 2), which represents the type of this operation.

If type = 1, there will be 3 more integers l, r, x (1 ≤ l ≤ r ≤ n; 1 ≤ x ≤ 108) in this line, describing an operation 1.

If type = 2, there will be 2 more integers l, r (1 ≤ l ≤ r ≤ n) in this line, describing an operation 2.

Output

For each operation 2, print a line containing the answer — sum of colorfulness.

Examples
input
3 3
1 1 2 4
1 2 3 5
2 1 3
output
8
input
3 4
1 1 3 4
2 1 1
2 2 2
2 3 3
output
3
2
1
input
10 6
1 1 5 3
1 2 7 9
1 10 10 11
1 3 8 12
1 1 10 3
2 1 10
output
129
Note

In the first sample, the color of each unit is initially [1, 2, 3], and the colorfulness is [0, 0, 0].

After the first operation, colors become [4, 4, 3], colorfulness become [3, 2, 0].

After the second operation, colors become [4, 5, 5], colorfulness become [3, 3, 2].

So the answer to the only operation of type 2 is 8.


题意:区间修改颜色,colorfulness+=颜色差的绝对值,区间查询colorfulness


线段树区间更新和区间查询

col记录颜色,0说明颜色不同;sum是colorfulness;lazy记录增量(colorfulness的增量)

更新的时候遇到相同颜色的被包含的区间直接更新,否则下传标记更新孩子然后合并

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#define m ((l+r)>>1)
#define lson o<<1,l,m
#define rson o<<1|1,m+1,r
#define lc o<<1
#define rc o<<1|1
using namespace std;
typedef long long ll;
const int N=5e5+5,INF=2e9+5;
inline int read(){
    char c=getchar();int x=0,f=1;
    while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
    while(c>='0'&&c<='9'){x=x*10+c-'0';c=getchar();}
    return x*f;
}
int n,q,op,ql,qr,x;
struct node{
    ll sum,lazy,col;
}t[N<<1];
void merge(int o){
    t[o].col=t[lc].col!=t[rc].col?0:t[lc].col;
    t[o].sum=t[lc].sum+t[rc].sum;
}
void build(int o,int l,int r){
    if(l==r) t[o].col=l;
    else{
        build(lson);
        build(rson);
    }
}
void pushDown(int o,int len){
    if(t[o].col){
        t[lc].col=t[rc].col=t[o].col;
        t[lc].lazy+=t[o].lazy;
        t[rc].lazy+=t[o].lazy;
        t[lc].sum+=t[o].lazy*(len-(len>>1));
        t[rc].sum+=t[o].lazy*(len>>1);
        
        t[o].col=t[o].lazy=0;
    }
}
void update(int o,int l,int r,int ql,int qr,ll v){//printf("update %d %d %d
",o,l,r);
    if(ql<=l&&r<=qr&&t[o].col){
        t[o].sum+=(r-l+1)*abs(v-t[o].col);
        t[o].lazy+=abs(v-t[o].col);
        t[o].col=v;
    }else{
        pushDown(o,r-l+1);
        if(ql<=m) update(lson,ql,qr,v);
        if(m<qr) update(rson,ql,qr,v);
        merge(o);
    }
}
ll query(int o,int l,int r,int ql,int qr){
    if(ql<=l&&r<=qr) return t[o].sum;
    else{
        pushDown(o,r-l+1);
        ll ans=0;
        if(ql<=m) ans+=query(lson,ql,qr);
        if(m<qr) ans+=query(rson,ql,qr);
        return ans;
    }
}
int main(){
    n=read();q=read();
    build(1,1,n);
    for(int i=1;i<=q;i++){
        op=read();ql=read();qr=read();
        if(op==1){x=read();update(1,1,n,ql,qr,x);}
        else printf("%I64d 
",query(1,1,n,ql,qr)); 
    }
}
原文地址:https://www.cnblogs.com/candy99/p/6068217.html