Avito Code Challenge 2018 E. Addition on Segments(线段树+背包)

题目链接:http://codeforces.com/contest/981/problem/E


线段树维护每个询问,然后统计每个区间中出现了多少个点,一边下放标记一边做01背包即可,当然,一看数据是1e4就知道这题不简单,bitset了解一下


代码:

#include
#define pb push_back
using namespace std;
const int MAXN=1e4+5;
typedef bitset state;
struct seg
{
	#define lson l,mid,rt<<1
	#define rson mid+1,r,rt<<1|1
	vector E[MAXN<<2];
	void update(int L,int R,int val,int l,int r,int rt)
	{
		if(L<=l&&r<=R)
		{
			E[rt].pb(val);
			return ;
		}
		int mid=(l+r)>>1;
		if(L<=mid) update(L,R,val,lson);
		if(mid>1;
	dfs(l,mid,now<<1);dfs(mid+1,r,now<<1|1);
	cur=book[now];
}
vector res;
int main()
{
	//freopen("in.txt","r",stdin);
	//freopen("out.txt","w",stdout);
	int n,q;
	scanf("%d%d",&n,&q);
	for(int i=1;i<=q;i++)
	{
		int l,r,x;
		scanf("%d%d%d",&l,&r,&x);
		se.update(l,r,x,1,n,1);
	}
	cur=1;
	dfs(1,n,1);
	for(int i=1;i<=n;i++) 
		if(ans[i])
			res.pb(i);
	printf("%d\n",int(res.size()));
	for(auto i:res)
		printf("%d ",i);
	printf("\n");
	return 0;
}

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