Submission #296775

#	Time	Username	Problem	Language	Result	Execution time	Memory
296775		peti1234	Sorting (IOI15_sorting)	C++17	100 / 100	399 ms	16612 KiB

sorting

#include <bits/stdc++.h>

using namespace std;
const int c=200002;
int lo, hi, mid, st=0, a[c], ia[c], b[c], ib[c], cs1, cs2;
vector<int> e, f;
void acsere() {swap(ia[a[cs1]], ia[a[cs2]]), swap(a[cs1], a[cs2]);}
void bcsere() {swap(ib[b[cs1]], ib[b[cs2]]), swap(b[cs1], b[cs2]);}
int findSwapPairs(int n, int s[], int m, int x[], int y[], int p[], int q[]) {
    lo=-1, hi=n;
    while(hi-lo>1) {
        mid=(hi+lo)/2, st=0;
        for (int i=0; i<n; i++) a[i]=s[i], b[i]=i, ia[s[i]]=i, ib[i]=i;
        e.clear(), f.clear();
        for (int i=mid-1; i>=0; i--) swap(ib[b[x[i]]], ib[b[y[i]]]), swap(b[x[i]], b[y[i]]);
        cs1=x[0], cs2=y[0];
        if (mid) acsere(), bcsere();
        for (int i=0; i<n; i++) {
            if (ia[i]!=ib[i]) {
                cs1=ia[i], cs2=ib[i];
                e.push_back(cs1), f.push_back(cs2);
                acsere();
                st++;
                if (st<mid) {
                cs1=x[st], cs2=y[st];
                acsere(), bcsere();
                }
            }
        }
        while(st<mid) e.push_back(0), f.push_back(0), st++;
        if (st<=mid) {
            hi=mid;
            for (int i=0; i<mid; i++) p[i]=e[i], q[i]=f[i];
        }
        else lo=mid;
    }
    return hi;
}

Compilation message (stderr)

sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:9:39: warning: unused parameter 'm' [-Wunused-parameter]
    9 | int findSwapPairs(int n, int s[], int m, int x[], int y[], int p[], int q[]) {
      |                                   ~~~~^

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