【划分树+二分】HDU 4417 Super Mario

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第一次耍划分树。。。
模板是找第ｋ小的
#include <stdio.h>#include <string.h>#include <stdlib.h>#include <math.h>#include <string>#include <iostream>#include <algorithm>using namespace std;#include <queue>#include <stack>#include <vector>#include <deque>#include <set>#include <map>typedef long long LL;const int MAXN = 100999;//点数的最大值const int MAXM = 1000010;//边数的最大值const LL INF = 1152921504;/** 划分树(查询区间第k小)*/int tree[20][MAXN];//表示每层每个位置的值int sorted[MAXN];//已经排序好的数int toleft[20][MAXN];//toleft[p][i]表示第p层从1到i有数分入左边void build(int l,int r,int dep){    if(l == r)return;    int mid = (l+r)>>1;    int same = mid - l + 1;//表示等于中间值而且被分入左边的个数    for(int i = l; i <= r; i++) //注意是l,不是one        if(tree[dep][i] < sorted[mid])            same--;    int lpos = l;    int rpos = mid+1;    for(int i = l; i <= r; i++)    {        if(tree[dep][i] < sorted[mid])            tree[dep+1][lpos++] = tree[dep][i];        else if(tree[dep][i] == sorted[mid] && same > 0)        {            tree[dep+1][lpos++] = tree[dep][i];            same--;        }        else            tree[dep+1][rpos++] = tree[dep][i];        toleft[dep][i] = toleft[dep][l-1] + lpos - l;    }    build(l,mid,dep+1);    build(mid+1,r,dep+1);}//查询区间第k小的数,[L,R]是大区间,[l,r]是要查询的小区间int query(int L,int R,int l,int r,int dep,int k){    if(l == r)return tree[dep][l];    int mid = (L+R)>>1;    int cnt = toleft[dep][r] - toleft[dep][l-1];    if(cnt >= k)    {        int newl = L + toleft[dep][l-1] - toleft[dep][L-1];        int newr = newl + cnt - 1;        return query(L,mid,newl,newr,dep+1,k);    }    else    {        int newr = r + toleft[dep][R] - toleft[dep][r];        int newl = newr - (r-l-cnt);        return query(mid+1,R,newl,newr,dep+1,k-cnt);    }}int main(){    int n,m,t,cas=1; //   freopen("in.txt","r",stdin);    scanf("%d",&t);    while(t--)    {        scanf("%d%d",&n,&m);        memset(tree,0,sizeof(tree));        for(int i = 1; i <= n; i++)        {            scanf("%d",&tree[0][i]);            sorted[i] = tree[0][i];        }        sort(sorted+1,sorted+n+1);        build(1,n,0);        int l,r,num;        printf("Case %d:\n",cas++);        while(m--)        {            scanf("%d%d%d",&l,&r,&num);            l++,r++;            int y=r-l+1,z=1;//边界            while(z<=y)            {                int x=(z+y)>>1;                int sum=query(1,n,l,r,0,x);                if(sum<=num)                    z=x+1;                else                    y=x-1;            }            z=r-l+1-z+1;            printf("%d\n",r-l+1-z);        }    }    return 0;}
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