Submission #306818

#	Time	Username	Problem	Language	Result	Execution time	Memory
306818		vipghn2003	Gondola (IOI14_gondola)	C++14	50 / 100	62 ms	3576 KiB

gondola

#include "gondola.h"
#include<bits/stdc++.h>
#define fi first
#define se second
#define pii pair<int,int>
#define mp make_pair
using namespace std;

const int mod=1e9+7;
const int N=1e5+5;
int ST[4*N],lazy[4*N];

void dolazy(int id,int l,int r)
{
    if(lazy[id]==0) return ;
    ST[id]+=lazy[id];
    if(l!=r)
    {
        lazy[id*2]+=lazy[id];
        lazy[id*2+1]+=lazy[id];
    }
    lazy[id]=0;
}

void update(int id,int l,int r,int u,int v,int val)
{
    dolazy(id,l,r);
    if(v<l||u>r) return ;
    if(u<=l&&r<=v)
    {
        ST[id]+=val;
        if(l!=r)
        {
            lazy[id*2]+=val;
            lazy[id*2+1]+=val;
        }
        return ;
    }
    int mid=(l+r)/2;
    update(id*2,l,mid,u,v,val);
    update(id*2+1,mid+1,r,u,v,val);
    ST[id]=min(ST[id*2],ST[id*2+1]);
}

int Power(int x,int n)
{
    if(!n) return 1;
    if(n%2) return 1ll*Power(x,n-1)*x%mod;
    int tmp=Power(x,n/2);
    return 1ll*tmp*tmp%mod;
}

int expect[N*2],initSeq[N];
int replacement(int n, int gondolaSeq[], int replacementSeq[])
{
	int offs = 0;
	int dummy = 0;
	int mx = -1;
	memset(expect, -1, sizeof(expect));
	for(int i = 0; i < n; i++){
		if(gondolaSeq[i] <= n) offs = (n+i-gondolaSeq[i]+1) % n;
		else expect[gondolaSeq[i]] = i;
		if(gondolaSeq[i] > mx){
			mx = gondolaSeq[i];
			dummy = i;
		}
	}
	for(int i = 0; i < n; i++){
		initSeq[(i+offs) % n] = i+1;
	}
	int rpidx = 0;
	for(int i = n+1; i <= mx; i++){
		if(expect[i] == -1){
			replacementSeq[rpidx++] = initSeq[dummy];
			initSeq[dummy] = i;
		}else{
			replacementSeq[rpidx++] = initSeq[expect[i]];
			initSeq[expect[i]] = i;
		}
	}
	return rpidx;
}

int countReplacement(int n,int inputSeq[])
{
    memset(ST,0,sizeof ST);
    vector<int>b(n),cur;
    for(int i=0;i<n;i++) inputSeq[i]--;
    int res=0;
    int val=0;
    for(int j=0;j<n;j++) if(inputSeq[j]>(n-1)) cur.push_back(inputSeq[j]-n+1);
    if(cur.empty()) val=1;
    else
    {
        sort(cur.begin(),cur.end());
        int sz=cur.size();
        val=Power(sz,cur[0]-1);
        for(int j=1;j<sz;j++)
        {
            if(cur[j]==cur[j-1])
            {
                val=0;
                break;
            }
            val=1ll*val*Power(sz-j,cur[j]-cur[j-1]-1)%mod;
        }
    }
    for(int i=0;i<n;i++) update(1,0,n-1,i,i,inputSeq[i]-i);
    for(int i=0;i<n;i++)
    {
        dolazy(1,0,n-1);
        if(ST[1]>=0) res=(res+val)%mod;
        update(1,0,n-1,0,n-1,-1);
        update(1,0,n-1,n-1-i,n-1-i,n);
    }
    return res;
}

int valid(int n,int inputSeq[])
{
    return countReplacement(n,inputSeq)!=0;
}
/*
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    cin>>n;
    int a[n];
    for(int i=0;i<n;i++) cin>>a[i];
    cout<<countReplacement(n,a);
}
*/

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 20 / 20
• Subtask 7: 5 / 5
• Subtask 8: 0 / 15
• Subtask 9: 0 / 15
• Subtask 10: 0 / 10