题解 | #小欧安排座位#

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll, ll>PII;
const int N = 2e5 + 10;
const int MOD = 998244353;
const int INF = 0X3F3F3F3F;
const int dx[] = {-1, 1, 0, 0, -1, -1, +1, +1};
const int dy[] = {0, 0, -1, 1, -1, +1, -1, +1};
const int M = 1e6 + 10;

int a[N];//记录独特的
int fa[N];//记录自己的座位
int main()
{
	int n;
	string s;
	cin >> n >> s;
	s = ' ' + s;
	int k = 0;
	for(int i = 1; i <= n; i ++)
	{
		if(s[i] == '1') a[++ k] = i;//找出来独特的
		else{
			fa[i] = i;
		}
	}
	if(k == 1)
	{
		for(int i = 1; i <= n; i ++) cout << i << " ";
	}
	else {
		if(k & 1)//是奇数取出前三个，后面的两两交换
		{
		    int o1 = a[1], o2 = a[2], o3 = a[3];
			fa[o1] = o2, fa[o2] = o3, fa[o3] = o1;
			for(int i = 4; i <= k; i += 2)
			{
				int x = a[i], y = a[i + 1];
				fa[x] = y;
				fa[y] = x;
			}
		}
		else {//偶数两两交换即可
			for(int i = 1; i <= k; i += 2)
			{
				int x = a[i], y = a[i + 1];
				fa[x] = y;
				fa[y] = x;
			}
		}
		for(int i = 1; i <= n; i ++)
		{
			cout << fa[i] << " ";//统一输出
		}
	}
}