[POI2011]MET-Meteors 整体二分_树状数组_卡常

线段树肯定会 TLE 的,必须要用树状数组.

Code:

// luogu-judger-enable-o2
#include <cstdio>
#include <algorithm>
#include <vector> 
#include <cstring>
#include <cctype>
#define setIO(s) freopen(s".in","r",stdin)
#define maxn 300009
#define ll long long
using namespace std;
vector<int>G[maxn]; 
int n,m,k,cnt[maxn],left[maxn<<1],right[maxn<<1],que[maxn],result[maxn]; 
int tl[maxn],tr[maxn]; 
int current[maxn],cost[maxn],w[maxn<<1]; 
inline int read()
{
    int k=0,f=1;char c=getchar();
    for(;!isdigit(c);c=getchar()) if(c=='-')f=-1;
    for(;isdigit(c);c=getchar()) k=k*10+c-'0';return f*k; 
}
struct Segment_Tree{
    ll sumv[maxn<<2],lazy[maxn<<2];
    #define lson (o<<1)
    #define rson (o<<1)|1
    void mark(int l,int r,int o,int delta)
    {
        sumv[o]+=delta*(r-l+1);
        lazy[o]+=delta;
    }
    int lowbit(int x){ return x&(-x); }
    void update(int l,int r,int L,int R,int o,int k){
        while(L<=r) sumv[L]+=k,L+=lowbit(L);
        ++R;
        while(R<=r) sumv[R]-=k,R+=lowbit(R); 
    }
    ll query(int l,int r,int pos,int pos2,int o){ 
        ll sum=0;
        while(pos>0) sum+=sumv[pos],pos-=lowbit(pos);
        return sum; 
    }
}tree;
void solve(int x,int y,int l,int r){
    if(x>y||l>r) return;
    if(l==r){ 
        for(int i=x;i<=y;++i) result[que[i]]=l; 
        return; 
    }
    int mid=(l+r)>>1,p=0,q=0,qcnt; 
    ll s; 
    for(int i=l;i<=mid;++i) {
        for(int cur=cnt[i-1]+1;cur<=cnt[i];++cur) { 
            tree.update(1,m,left[cur],right[cur],1,w[cur]);
        }
    }
    for(int i=x;i<=y;++i){
        int u=que[i];
        int siz=G[u].size(); 
        s=current[u]; 
        for(int j=0;j<siz&&s<=(ll)cost[u];++j) 
            s+=tree.query(1,m,G[u][j],G[u][j],1); 
        if(s>=cost[u]) tl[++p]=u;
        else tr[++q]=u,current[u]=s; 
    }
    for(int i=l;i<=mid;++i)
        for(int cur=cnt[i-1]+1;cur<=cnt[i];++cur) 
            tree.update(1,m,left[cur],right[cur],1,-w[cur]); 
    qcnt=x-1;
    for(int i=1;i<=p;++i) que[++qcnt]=tl[i];
    for(int i=1;i<=q;++i) que[++qcnt]=tr[i];
    solve(x,x+p-1,l,mid),solve(x+p,y,mid+1,r); 
}
int main(){
    //setIO("input");
    n=read(),m=read(); 
    for(int i=1;i<=m;++i) 
    {
        int a=read();  
        G[a].push_back(i); 
    }
    for(int i=1;i<=n;++i) cost[i]=read(); 
    k=read(); 
    int idx=0; 
    for(int i=1;i<=k;++i){
        int l,r,c; 
        l=read(),r=read(),c=read(); 
        if(l<=r) cnt[i]=++idx,left[idx]=l,right[idx]=r,w[idx]=c; 
        else {
            cnt[i]=++idx; 
            left[idx]=l,right[idx]=m,w[idx]=c;
            cnt[i]=++idx; 
            left[idx]=1,right[idx]=r,w[idx]=c; 
        }
    }
    for(int i=1;i<=n;++i) que[i]=i;
    cnt[++k]=++idx;
    left[idx]=1,right[idx]=m,w[idx]=(int)1e9; 
    solve(1,n,1,k);  
    for(int i=1;i<=n;++i) 
        if(result[i]==k) printf("NIE
"); 
        else printf("%d
",result[i]); 
    return 0; 
}

  

原文地址:https://www.cnblogs.com/guangheli/p/10264266.html