51nod 1364 最大字典序排列

贪心+线段树+二分

姿势有点问题。。加了快速读写才不T。。。。

#include<bits/stdc++.h>
using namespace std;

const int MAXN=100100;
int a[MAXN],pos[MAXN];
struct node
{
int l,r;
int nsum;
}segtree1[MAXN<<2],segtree2[MAXN<<2];

void build1(int i,int l,int r)
{
segtree1[i].l=l;
segtree1[i].r=r;
if(l==r)
{
segtree1[i].nsum=a[l];
return;
}
int mid=(l+r)>>1;
build1(i<<1,l,mid);
build1(i<<1|1,mid+1,r);
segtree1[i].nsum=max(segtree1[i<<1].nsum,segtree1[i<<1|1].nsum);
}

void add1(int i,int a,int c)
{
if(segtree1[i].l==a&&segtree1[i].r==a)
{
segtree1[i].nsum+=c;
return;
}
int mid=(segtree1[i].l+segtree1[i].r)>>1;
if(a<=mid)
add1(i<<1,a,c);
else if(a>mid)
add1(i<<1|1,a,c);
segtree1[i].nsum=max(segtree1[i<<1].nsum,segtree1[i<<1|1].nsum);
}

long long query1(int i,int a,int b)
{
if(segtree1[i].l==a&&segtree1[i].r==b)
return segtree1[i].nsum;
int mid=(segtree1[i].l+segtree1[i].r)>>1;
if(b<=mid)
return query1(i<<1,a,b);
else if(a>mid)
return query1(i<<1|1,a,b);
else
return max(query1(i<<1,a,mid),query1(i<<1|1,mid+1,b));
}

void build2(int i,int l,int r)
{
segtree2[i].l=l;
segtree2[i].r=r;
if(l==r)
{
segtree2[i].nsum=1;
return;
}
int mid=(l+r)>>1;
build2(i<<1,l,mid);
build2(i<<1|1,mid+1,r);
segtree2[i].nsum=segtree2[i<<1].nsum+segtree2[i<<1|1].nsum;
}

void add2(int i,int a,int c)
{
if(segtree2[i].l==a&&segtree2[i].r==a)
{
segtree2[i].nsum+=c;
return;
}
int mid=(segtree2[i].l+segtree2[i].r)>>1;
if(a<=mid)
add2(i<<1,a,c);
else if(a>mid)
add2(i<<1|1,a,c);
segtree2[i].nsum=segtree2[i<<1].nsum+segtree2[i<<1|1].nsum;
}

long long query2(int i,int a,int b)
{
if(segtree2[i].l==a&&segtree2[i].r==b)
return segtree2[i].nsum;
int mid=(segtree2[i].l+segtree2[i].r)>>1;
if(b<=mid)
return query2(i<<1,a,b);
else if(a>mid)
return query2(i<<1|1,a,b);
else
return query2(i<<1,a,mid)+query2(i<<1|1,mid+1,b);
}

void read(int&a){
char ch;while(!((ch=getchar())>='0')&&(ch<='9'));
a=ch-'0';while(((ch=getchar())>='0')&&(ch<='9'))a*=10,a+=ch-'0';
}

inline void prin_d(int x)
{
if (x > 9)
{
prin_d(x / 10);
}
putchar(x % 10 + '0');
return ;
}

int main()
{
int n,k,i,tmp,lef,rig,mid;
while(~scanf("%d%d",&n,&k))
{
for(i=1;i<=n;i++)
read(a[i]);
for(i=1;i<=n;i++)
pos[a[i]]=i;
build1(1,1,n);
build2(1,1,n);
for(i=1;i<=n;i++)
{
lef=1;rig=n;
while(lef<=rig)
{
mid=(lef+rig)>>1;
if(query2(1,1,mid)<=k)
lef=mid+1;
else
rig=mid-1;
}
lef=min(lef,n);
tmp=query1(1,1,lef);
prin_d(tmp);
puts("");
k-=query2(1,1,pos[tmp])-1;
add1(1,pos[tmp],-(1<<29));
add2(1,pos[tmp],-1);
}
}
}