Submission #227701

#	Time	Username	Problem	Language	Result	Execution time	Memory
227701		emil_physmath	Crazy old lady (IZhO13_crazy)	C++17	100 / 100	66 ms	640 KiB

crazy

#include <algorithm>
#include <iostream>
#include <vector>
#include <set>
using namespace std;

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int t;
    cin >> t;
    while (t--)
    {
        int n;
        cin >> n;
        vector<int> a(n);
        for (int i = 0; i < n; ++i)
        {
            cin >> a[i];
            --a[i];
        }
        set<int> res;
        for (int x = 0; x < n; ++x)
        {
            bool poss = true;
            vector<int> q;
            q.push_back(x);
            for (int i = 0; i < n; ++i)
                if (i != x)
                    q.push_back(i);
            vector<bool> used(n);
            used[a[0]] = true;
            for (int i = 1; i < n; ++i)
            {
                if (!used[q[i]] && a[i] != q[i])
                {
                    poss = false;
                    break;
                }
                used[a[i]] = true;
            }
            if (poss)
                res.insert(x);
        }
        if (res.size() == 1)
            cout << *res.begin() + 1 << '\n';
        else
            cout << 0 << '\n';
    }
}

• Subtask 1: 100 / 100