C. Little Elephant and Shifts
Time Limit: 20 Sec
Memory Limit: 256 MB
题目连接
http://codeforces.com/problemset/problem/220/C
Description
The distance between permutations a and b is the minimum absolute value of the difference between the positions of the occurrences of some number in a and in b. More formally, it's such minimum |i - j|, that ai = bj.
A cyclic shift number i (1 ≤ i ≤ n) of permutation b consisting from n elements is a permutation bibi + 1... bnb1b2... bi - 1. Overall a permutation has n cyclic shifts.
The Little Elephant wonders, for all cyclic shifts of permutation b, what is the distance between the cyclic shift and permutation a?
Input
The first line contains a single integer n (1 ≤ n ≤ 105) — the size of the permutations. The second line contains permutation a as n distinct numbers from 1 to n, inclusive. The numbers are separated with single spaces. The third line contains permutation b in the same format.
Output
In n lines print n integers — the answers for cyclic shifts. Print the answers to the shifts in the order of the shifts' numeration in permutation b, that is, first for the 1-st cyclic shift, then for the 2-nd, and so on.
Sample Input
2
1 2
2 1
Sample Output
1
0
HINT
题意
给你一个a数组,一个b数组
都只含1-n
俩数组的距离定义为,if(a[i]==b[j])dis=min(dis,abs(j-i))
然后对于每一个b的排列,让你输出距离
题解:
用multiset模拟一下就好了
对了,如果用multiset.erase(iterator)这样是只会删除一个的
如果multiset.erase(x),x是一个number的话,这样会把等于x的都删除
代码
#include <cstdio> #include <cmath> #include <cstring> #include <ctime> #include <iostream> #include <algorithm> #include <set> #include <vector> #include <sstream> #include <queue> #include <typeinfo> #include <fstream> #include <map> #include <stack> typedef long long ll; using namespace std; //freopen("D.in","r",stdin); //freopen("D.out","w",stdout); #define sspeed ios_base::sync_with_stdio(0);cin.tie(0) #define test freopen("test.txt","r",stdin) #define maxn 1050005 #define mod 10007 #define eps 1e-9 const int inf=0x3f3f3f3f; const ll infll = 0x3f3f3f3f3f3f3f3fLL; inline ll read() { ll x=0,f=1;char ch=getchar(); while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();} while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();} return x*f; } //************************************************************************************** int a[maxn]; int b[maxn]; multiset<int> s; multiset<int>::iterator it; int ans; int main() { int n=read(); for(int i=0;i<n;i++) { int x=read(); a[x]=i; } for(int i=0;i<n;i++) { b[i]=read(); s.insert(i-a[b[i]]); } for(int i=0;i<n;i++) { ans=inf; it=s.lower_bound(i); if(it!=s.end()) ans=min(ans,*it-i); if(it!=s.begin()) ans=min(ans,i-*(--it)); printf("%d ",ans); it=s.find(i-a[b[i]]); s.erase(it); s.insert(i-a[b[i]]+n); } }