Submission #238896

#	Time	Username	Problem	Language	Result	Execution time	Memory
238896		Sorting	Secret Permutation (RMI19_permutation)	C++14	0 / 100	5 ms	384 KiB

permutation

#include <bits/stdc++.h>
//#include "permutationc.h"

using namespace std;

int query(int v[]);
int query(vector<int> v);
void answer(int v[]);
void answer(vector<int> v);

void solve(int n){
    vector<int> v;
    for(int i = 1; i <= n; ++i)
        v.push_back(i);

    int best_diff = 0, best_idx = 1;
    for(int i = 2; i < n; ++i){
        swap(v[i], v[n - 1]);
        int curr = query(v);
        swap(v[1], v[n - 1]);
        int after = query(v);
        swap(v[1], v[n - 1]);
        swap(v[i], v[n - 1]);

        int curr_diff = after - curr;
        if(curr_diff > best_diff){
            best_diff = curr_diff;
            best_idx = i;
        }
    }

    int best_val = best_idx + 1;
    //cout << best_idx << " best_idx" << endl;

    swap(v[best_idx], v[0]);
    vector<int> diff(n);
    diff[1] = 0;
    for(int i = 2; i < n; ++i){
        swap(v[i], v[n - 1]);
        int curr = query(v);
        swap(v[1], v[n - 1]);
        int after = query(v);
        swap(v[1], v[n - 1]);
        swap(v[i], v[n - 1]);

        diff[i] = after - curr;
    }

    int min_diff = 100000;
    for(int i = 1; i < n; ++i)
        min_diff = min(diff[i], min_diff);

    for(int i = 1; i < n; ++i){
        diff[i] -= min_diff;
        diff[i] += 2;
    }
    diff[0] = 1;
    swap(diff[best_idx], diff[0]);

    answer(diff);
}

Compilation message (stderr)

permutation.cpp: In function 'void solve(int)':
permutation.cpp:32:9: warning: unused variable 'best_val' [-Wunused-variable]
     int best_val = best_idx + 1;
         ^~~~~~~~
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]
   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]
   fscanf(stdin, "%d", &N);
   ~~~~~~^~~~~~~~~~~~~~~~~

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