Submission #1123994

#	Time	Username	Problem	Language	Result	Execution time	Memory
1123994		allin27x	Sorting (IOI15_sorting)	C++17	74 / 100	1094 ms	6712 KiB

sorting

#include <bits/stdc++.h>
#include "sorting.h"
using namespace std;


int solveforM(int n, int st[], int m, int x[], int y[], int p[], int q[]) {
	vector<int> a(n); iota(a.begin(), a.end(), 0);
	vector<int> s(n); for (int i=0; i<n; i++) s[i] = st[i];
	for (int i=m-1; i>=0; i--) swap(a[x[i]], a[y[i]]);
	for (int ind=0; ind<m; ind++) {
		int f =0; for (int i=0; i<n; i++) if (s[i] != i) f++;
		if (!f) return ind;
		p[ind] = 0; q[ind] = 0;
		swap(a[x[ind]], a[y[ind]]); swap(s[x[ind]], s[y[ind]]);
		f = 0;
		for (int i=0; i<n; i++) {
			if (f) break;
			if (a[i] != s[i]) {
				for (int j=0; j<n; j++) {
					if (a[j] == s[i]) {
						p[ind] = i; q[ind] = j;
						swap(s[i], s[j]);
						f = 1;
						break;
					}
				}
			}
		}
	}
	int f =0; for (int i=0; i<n; i++) if (s[i] != i) f++;
	if (f) return 1e9;
	return m;

}
int findSwapPairs(int n, int s[], int m, int x[], int y[], int p[], int q[]) {
	int l = 0; int r = m;
	while (l<r) {
		int md = (l+r)/2;
		if (solveforM(n,s, md, x,y,p,q) <m) r = md; else l = md+1;
	}
	solveforM(n,s, l, x,y,p,q);
	return l;
}

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