Submission #685445

#	Time	Username	Problem	Language	Result	Execution time	Memory
685445		dranaya_dusha	Secret Permutation (RMI19_permutation)	C++17	0 / 100	1 ms	336 KiB

permutation

//#pragma GCC optimize ("Ofast")
#include <bits/stdc++.h>
////#define int long long
//#define mp make_pair
//#define pb push_back
//#define fi first
//#define se second
//#define pii pair <int, int>


#include "permutation.h"
using namespace std;
vector<int> ans;
vector<int> used;
bool check (vector<int> &q, vector<int> &v, int p, int n)
{
    used[ans[v[p]-1]]=1;
    if (p==n-1)
    {
        answer(ans);
        exit(0);
    }
    else{
        if (ans[v[p]-1]+q[p]<=n && !used[ans[v[p]-1]+q[p]]){
            ans[v[p+1]-1]=ans[v[p]-1]+q[p];
           // used[ans[v[p]-1]+q[i]]=1;
           check(q, v, p+1, n);
        }
        else if (ans[v[p]-1]-q[p]>0 && !used[ans[v[p]-1]-q[p]])
        {
            ans[v[p+1]-1]=ans[v[p]-1]-q[p];
            check(q, v, p+1, n);
           // used[ans[v[p]-1]-q[p]]=1;
        }
        used[ans[v[p]-1]]=0;
        ans[v[p]-1]=0;
    }
}


void solve(int n) {

    vector<int> v;
    for (int i=1; i<=n; i++)
        v.push_back(i);
    srand(time(NULL));
    random_shuffle(v.begin(), v.end());
    vector<int> q(n);
    for(int i=0;i<n;i++){
        rotate(v.begin(),v.begin()+1,v.end());
        q[i] = query(v);
    }
//    for (int i=0; i<n; i++)
//        cout << q[i] << ' ';
    rotate(v.begin(),v.begin()+1,v.end());
    int sum=0;
    for(int i=0;i<n;i++){
        sum+=q[i];
    }
    sum/=(n-1);
    for(int i=0;i<n;i++) q[i]=(sum-q[i]);
    rotate(q.begin(),q.begin()+1,q.end());

    ans.assign(n, 0);
//        for (int i=0; i<n; i++)
//        cout << q[i] << ' ';
//        cout << endl;
//        for (int i=0; i<n; i++)
//        cout << v[i] << ' ';
//        cout << endl;
    for (int i=1; i<=n; i++)
    {
        used.assign(n+1, 0);
        ans.assign(n, 0);
        ans[0]=i;
        check(q, v, 0, n);
    }
}

Compilation message (stderr)

permutation.cpp: In function 'bool check(std::vector<int>&, std::vector<int>&, int, int)':
permutation.cpp:36:20: warning: control reaches end of non-void function [-Wreturn-type]
   36 |         ans[v[p]-1]=0;
stub.cpp: In function 'int query(int*)':
stub.cpp:15:9: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |   fscanf(stdin, "%d", &x);
      |   ~~~~~~^~~~~~~~~~~~~~~~~
stub.cpp: In function 'int main(int, char**)':
stub.cpp:48:9: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |   fscanf(stdin, "%d", &N);
      |   ~~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 35
• Subtask 3: 0 / 50