Submission #774071

#	Time	Username	Problem	Language	Result	Execution time	Memory
774071		Dan4Life	Xylophone (JOI18_xylophone)	C++17	0 / 100	0 ms	208 KiB

xylophone

#include "xylophone.h"
#include <bits/stdc++.h>
using namespace std;
int a[5010], _ok[20000];int *ok = _ok+10000;
int Query(int i, int j){return query(min(i,j),max(i,j));}
void Answer(int x, int v){answer(x,v); a[x]=v; ok[v]=1; }
 
void solve(int n) {
    int l = 1, r = n-1;
    while(l<r){
        int m = (l+r+1)/2;
        if(Query(m,n)==n-1) l=m;
        else r=m-1;
    }
    for(int i = -2*n; i <= 2*n; i++) 
		ok[i]=(i<1 or i>n);
    Answer(l,1);
	for(int x : {1,-1}){
		for(int i = l-x; i>=1; i--){
			int dif = Query(i,i+x);
			int x1 = a[i+x]-dif, x2 = a[i+x]+dif;
			if(ok[x1]) swap(x1,x2);
			if(ok[x2]) Answer(i,x1);
			else{
				int dif2 = Query(i,i+2*x);
				if(max({x1,a[i+x],a[i+2*x]})-min({x1,a[i+x],a[i+2*x]})==dif2) Answer(i,x1);
				else Answer(i,x2);
			}
		}
	}
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 36
• Subtask 3: 0 / 53