Codeforces 323C Two permutations
題目描述
You are given two permutations pp and qq , consisting of nn elements, and mm queries of the form: l_{1},r_{1},l_{2},r_{2}l1?,r1?,l2?,r2? $ (l_{1}<=r_{1}; l_{2}<=r_{2}) $ . The response for the query is the number of such integers from 11 to nn , that their position in the first permutation is in segment [l_{1},r_{1}][l1?,r1?] (borders included), and position in the second permutation is in segment [l_{2},r_{2}][l2?,r2?](borders included too).
A permutation of nn elements is the sequence of nn distinct integers, each not less than 11 and not greater than nn .
Position of number vv (1<=v<=n)(1<=v<=n) in permutation g_{1},g_{2},...,g_{n}g1?,g2?,...,gn? is such number ii , that g_{i}=vgi?=v .
輸入輸出格式
輸入格式:
The first line contains one integer n\ (1<=n<=10^{6})n (1<=n<=106) , the number of elements in both permutations. The following line contains nn integers, separated with spaces: p_{1},p_{2},...,p_{n}\ (1<=p_{i}<=n)p1?,p2?,...,pn? (1<=pi?<=n) . These are elements of the first permutation. The next line contains the second permutation q_{1},q_{2},...,q_{n}q1?,q2?,...,qn? in same format.
The following line contains an integer m\ (1<=m<=2·10^{5})m (1<=m<=2?105) , that is the number of queries.
The following mm lines contain descriptions of queries one in a line. The description of the ii -th query consists of four integers: a,b,c,d\ (1<=a,b,c,d<=n)a,b,c,d (1<=a,b,c,d<=n) . Query parameters l_{1},r_{1},l_{2},r_{2}l1?,r1?,l2?,r2? are obtained from the numbers a,b,c,da,b,c,dusing the following algorithm:
- Introduce variable xx . If it is the first query, then the variable equals 00 , else it equals the response for the previous query plus one.
- Introduce function f(z)=((z-1+x)\ mod\ n)+1f(z)=((z?1+x) mod n)+1 .
- Suppose l_{1}=min(f(a),f(b)),r_{1}=max(f(a),f(b)),l_{2}=min(f(c),f(d)),r_{2}=max(f(c),f(d))l1?=min(f(a),f(b)),r1?=max(f(a),f(b)),l2?=min(f(c),f(d)),r2?=max(f(c),f(d)) .
輸出格式:
Print a response for each query in a separate line.
輸入輸出樣例
輸入樣例#1:3 3 1 2 3 2 1 1 1 2 3 3輸出樣例#1:
1輸入樣例#2:
4 4 3 2 1 2 3 4 1 3 1 2 3 4 1 3 2 1 1 4 2 3輸出樣例#2:
1 1 2
把第二個排列的數在第一個排列中對應的位置記一下,主席樹跑一跑就行了。
#include<iostream> #include<cstdio> #include<cstdlib> #include<cmath> #include<algorithm> #include<cstring> #define ll long long #define maxn 1000005 using namespace std; struct node{ node *lc,*rc; int s; }nil[maxn*30],*rot[maxn],*cnt; int a[maxn],n,ky,num[maxn]; int m,le,ri,k,preans=-1,ple,pri; char ch; inline int add(int x,int y,const int ha){ return (x+y)%ha; } node *update(node *u,int l,int r){ node *ret=++cnt; *ret=*u; ret->s++; if(l==r) return ret; int mid=l+r>>1; if(le<=mid) ret->lc=update(ret->lc,l,mid); else ret->rc=update(ret->rc,mid+1,r); return ret; } int query(node *u,node *v,int l,int r){ if(l>=le&&r<=ri) return v->s-u->s; int mid=l+r>>1,an=0; if(le<=mid) an+=query(u->lc,v->lc,l,mid); if(ri>mid) an+=query(u->rc,v->rc,mid+1,r); return an; } inline void prework(){ cnt=rot[0]=nil->lc=nil->rc=nil; nil->s=0; for(int i=1;i<=n;i++){ le=a[i]; rot[i]=update(rot[i-1],1,n); } } inline void solve(){ scanf("%d",&m); while(m--){ scanf("%d%d%d%d",&le,&ri,&ple,&pri); le=add(le,preans,n)+1; ri=add(ri,preans,n)+1; ple=add(ple,preans,n)+1; pri=add(pri,preans,n)+1; if(le>ri) swap(le,ri); if(ple>pri) swap(ple,pri); preans=query(rot[ple-1],rot[pri],1,n); printf("%d\n",preans); } } int main(){ scanf("%d",&n); int now; for(int i=1;i<=n;i++){ scanf("%d",&now); num[now]=i; } for(int i=1;i<=n;i++){ scanf("%d",&now); a[i]=num[now]; } prework(); solve(); return 0; }
Codeforces 323C Two permutations