题目传送
思路:
咦,比赛的时候暴力写岔了一个地方,没写出来
没有什么好讲的,暴力干就完事,题目中的k < 2n是迷惑人的,我直接暴力变成下面的数组,无论怎样都不会超过2n次
我们直接把这个数组变成 0 1 2 3 4 5 6 … n-2 n-1 即可
枚举目前的未出现的最小非负整数,然后添加到相应的位置,如果枚举出来的是n,那么我们就把他添加到一个i != arr[i]的位置即可
AC代码
#include <bits/stdc++.h>
inline long long read(){char c = getchar();long long x = 0,s = 1;
while(c < '0' || c > '9') {if(c == '-') s = -1;c = getchar();}
while(c >= '0' && c <= '9') {x = x*10 + c -'0';c = getchar();}
return x*s;}
using namespace std;
#define NewNode (TreeNode *)malloc(sizeof(TreeNode))
#define Mem(a,b) memset(a,b,sizeof(a))
#define lowbit(x) (x)&(-x)
const int N = 2e5 + 10;
const long long INFINF = 0x7f7f7f7f7f7f7f;
const int INF = 0x3f3f3f3f;
const double EPS = 1e-7;
const int mod = 1e9+7;
const double II = acos(-1);
const double PP = (II*1.0)/(180.00);
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> piil;
signed main()
{
std::ios::sync_with_stdio(false);
cin.tie(0),cout.tie(0);
// freopen("input.txt","r",stdin);
// freopen("output.txt","w",stdout);
int t;
cin >> t;
while(t--)
{
int n;
cin >> n;
int arr[n+5] = {0};
vector<int> v;
for(int i = 0;i < n;i++) cin >> arr[i];
while(1)
{
int flag = 1,b[n+5] = {0},Min = 0;
for(int i = 1;i < n;i++)
if(arr[i] < arr[i-1])
{flag = 0;break;}
if(flag) break;
for(int i = 0;i < n;i++) b[i] = arr[i];
sort(b,b+n);
for(int i = 0;i < n;i++)
if(b[i] == Min)
Min++;
if(Min == n)
{
int i = 0;
for(;i < n;i++)
if(i != arr[i])
break;
v.push_back(i);
arr[i] = Min;
}
else
{
v.push_back(Min);
arr[Min] = Min;
}
}
cout << v.size() << endl;
for(int i = 0;i < v.size();i++)
cout << v[i]+1 << " ";
cout << endl;
}
}