Submission #1028587

#	Time	Username	Problem	Language	Result	Execution time	Memory
1028587		vjudge1	Crazy old lady (IZhO13_crazy)	C++17	0 / 100	1 ms	604 KiB

crazy

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> 
 
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
 
using namespace std;
using namespace __gnu_pbds;
 
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define s second
#define int long long
#define pii pair<int,int>
 
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
 
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
 tree_order_statistics_node_update> ordered_set;
 
const int inf = 1e17 + 7;
const int mod = 1e9 + 7;
const int N = 3e5 + 5;
const int md = 998244353;

int binpow(int a, int b){
	if(b == 0)return 1;
	if(b % 2 == 0){
		int c = binpow(a,b/2);
		return (c*c)%mod;
	}
	return (binpow(a,b-1)*a)%mod;
}

int divi(int a, int b){
	return (a*(binpow(b,mod-2)))%mod;
}

int n,m,k;

void solve(){
	
	cin >> n;
	vector<int>v(n);
	for(auto &to:v)cin >> to;
	vector<int>ans;
	for(int i = 0;i<n;i++){
		vector<int>vis(n), vs(n);
		vis[v[i]] = 1;
		vs[i] = v[i];
		bool flag = true;
		for(int j = 0;j<n;j++){
			if(j == i)continue;
			if(vis[j+1] == 0){
				vis[j+1] = 1;
				vs[j] = j+1;
			}
			else if(vis[v[j]] == 0){
				vis[v[j]] = 1;
				vs[j] = v[j];
			}
			else flag = false;
		}
		if(!flag)continue;
		for(int j = 0;j<n;j++){
			if(vs[j] != v[j])flag = false;
		}
		if(!flag)continue;
		ans.pb(i+1);
	}
	//~ cout << ans.size() << " ";
	//~ for(auto to:ans)cout << to << " ";
	//~ cout << "\n";
	if(ans.size() != 1)cout << 0 << "\n";
	else cout << ans[0] << "\n";
	
}
/*
2
2
2 1
4
4 2 3 1 4

 */
 signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int tt=1;cin>>tt;
	while(tt--)solve();
 
}
 

• Subtask 1: 0 / 100