HZOI20190908 40 captain simulation run, shadow magic, flip a coin problem solution

Questions surface: https://www.cnblogs.com/Juve/articles/11487699.html

Captain Run:

Weight segment tree and dp

yy good

 

	tr[k<<1|1].mx+=tr[k].laz;
void pushup(int k){
	tr[k].mx=max(tr[k<<1].mx,tr[k<<1|1].mx);
}
int query_max(int k,int opl,int opr){
	int l=tr[k].l,r=tr[k].r;
	if(opl<=l&&r<=opr) return tr[k].mx;
	if(tr[k].laz) down(k);
	int mid=(l+r)>>1,res=0;
	if(opl<=mid) res=max(res,query_max(k<<1,opl,opr));
	if(opr>mid) res=max(res,query_max(k<<1|1,opl,opr));
	return res;
}
void update(int k,int opt,int val){
	int l=tr[k].l,r=tr[k].r;
	if(l==r){
		tr[k].mx=max(tr[k].mx,val);
		return ;
	}
	if(tr[k].laz) down(k);
	int mid=(l+r)>>1;
	if(opt<=mid) update(k<<1,opt,val);
	else update(k<<1|1,opt,val);
	pushup(k);
}
void change(int k,int opl,int opr){
	int l=tr[k].l,r=tr[k].r;
	if(opl<=l&&r<=opr){
		++tr[k].mx;
		++tr[k].laz;
		return ;
	}
	if(tr[k].laz) down(k);
	int mid=(l+r)>>1;
	if(opl<=mid) change(k<<1,opl,opr);
	if(opr>mid) change(k<<1|1,opl,opr);
	pushup(k);
}
signed main(){
	scanf("%d",&n);
	for(int i=1;i<=n;++i){
		scanf("%d%d",&a[i],&b[i]);
		lsh[++tot]=a[i],lsh[++tot]=b[i];
	}
	sort(lsh+1,lsh+tot+1);
	cnt=unique(lsh+1,lsh+tot+1)-lsh;
	for(int i=1;i<=n;++i){
		a[i]=lower_bound(lsh+1,lsh+cnt+1,a[i])-lsh;
		b[i]=lower_bound(lsh+1,lsh+cnt+1,b[i])-lsh;
	}
	build(1,1,cnt);
	for(int i=n;i>=1;--i){
		if(a[i]>b[i]){
			int p=query_max(1,1,b[i]-1)+1;
			update(1,b[i],p);
			change(1,b[i]+1,a[i]);
		}else{
			int p=query_max(1,1,a[i]-1)+1;
			update(1,b[i]+1,p);
		}
	}
	printf("%d\n",tr[1].mx);
    return 0;
}

 

toss a coin:

Fucks dp

 

#include<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
using namespace std;
const int MAXN=3005;
const int mod=998244353;
int l,len,f[MAXN][MAXN],s[MAXN];
char ch[MAXN];
signed main(){
	scanf("%s",ch+1);
    scanf("%d",&l);
    len=strlen(ch+1);
	//cout<<len<<endl;
	for(int i=1;i<=len;++i){
		f[i][0]=1;
		for(int j=i-1;j>=1;--j){
			if(ch[j]==ch[i]){
				s[i]=j;
				break;
			}
		}
	}
	//for(int i=1;i<=len;++i) cout<<s[i]<<endl;
    f[0][0]=1;
    for(int i=1;i <= len; ++ i) {
		for(int j=1;j<=l;++j){
			if(s[i]!=0) f[i][j]=((f[i-1][j]+f[i-1][j-1]-f[s[i]-1][j-1])%mod+mod)%mod;
			else f[i][j]=(f[i-1][j]+f[i-1][j-1])%mod;
		}
	}
	printf("%d\n",f[len][l]);
	return 0;
}