Submission #552889

#	Time	Username	Problem	Language	Result	Execution time	Memory
552889		elazarkoren	Sorting (IOI15_sorting)	C++17	0 / 100	5 ms	408 KiB

sorting

#include "sorting.h"
#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
//#define int ll
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vii;
typedef vector<bool> vb;

const int MAX_N = 2e5 + 5;

int x[MAX_N], y[MAX_N];
int n;

int cnt;

vi Compute(int i, vi s) {
    for (; i < cnt; i++) {
        swap(s[x[i]], s[y[i]]);
    }
    return s;
}

int findSwapPairs(int N, int S[], int m, int X[], int Y[], int p[], int q[]) {
    n = N;
    cnt = n;
    vi s(n);
    for (int i = 0; i < n; i++) s[i] = S[i];
    for (int i = 0; i < cnt; i++) x[i] = X[i], y[i] = Y[i];
    for (int i = 0; i < cnt; i++) {
//        swap(s[x[i]], s[y[i]]);
//        vi s2 = Compute(i + 1, s);
        vi s2 = s;
//        if (s != s2) {
//            cout << "";
//        }
        int v1, v2;
        for (int j = 0; j < n; j++) {
            if (s2[j] == i) {
                v1 = s2[i], v2 = s2[j];
            }
        }
        int ind1, ind2;
        for (ind1 = 0; s[ind1] != v1; ind1++);
        for (ind2 = 0; s[ind2] != v2; ind2++);
        p[i] = ind1, q[i] = ind2;
        swap(s[p[i]], s[q[i]]);
    }
    for (int i = 0; i < n; i++) s[i] = S[i];
    for (int i = 0; i < cnt; i++) {
        swap(s[x[i]], s[y[i]]);
        swap(s[p[i]], s[q[i]]);
    }
    for (int i = 0; i < n; i++) {
        if (s[i] != i) {
            return -1;
        }
    }
    return cnt;
}
//8
//3 5 6 2 1 7 0 4
//8
//0 1
//0 1
//0 1
//0 1
//0 1
//0 1
//0 1
//0 1

//5
//3 2 1 0 4
//5
//0 0
//0 0
//0 0
//0 0
//0 0

Compilation message (stderr)

sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:31:39: warning: unused parameter 'm' [-Wunused-parameter]
   31 | int findSwapPairs(int N, int S[], int m, int X[], int Y[], int p[], int q[]) {
      |                                   ~~~~^
sorting.cpp:52:32: warning: 'v2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   52 |         for (ind2 = 0; s[ind2] != v2; ind2++);
sorting.cpp:51:32: warning: 'v1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   51 |         for (ind1 = 0; s[ind1] != v1; ind1++);

• Subtask 1: 0 / 8
• Subtask 2: 0 / 12
• Subtask 3: 0 / 16
• Subtask 4: 0 / 18
• Subtask 5: 0 / 20
• Subtask 6: 0 / 26