#include <bits/stdc++.h>
#include "sorting.h"
//#include "grader.cpp"
using namespace std;
int n, m;
vector <int> s;
vector <pair <int, int> > w;
vector <pair <int, int> > swaps(vector <int> &a){
vector <bool> vis(n);
vector <pair <int, int> > swaps;
for(int i = 0 ; i < n ; i++){
if(vis[i]) continue;
vector <int> cycle;
int cur = i;
while(vis[cur] == 0){
cycle.push_back(cur);
vis[cur] = 1;
cur = a[cur];
}
for(int i = 1 ; i < (int)cycle.size() ; i++){
swaps.emplace_back(cycle[0], cycle[i]);
}
}
vector <int> b = a;
vector <pair <int, int> > ret;
for(auto &i : swaps){
ret.emplace_back(b[i.first], b[i.second]);
swap(b[i.first], b[i.second]);
}
return ret;
}
vector <pair <int, int> > check(int mid){
vector <int> a = s;
for(int i = 0 ; i < mid ; i++){
swap(a[w[i].first], a[w[i].second]);
}
auto c = swaps(a);
if((int)c.size() > mid){
return vector <pair <int, int> >(1, make_pair(-1, -1));
}
a = s;
vector <int> pos(n);
for(int i = 0 ; i < n ; i++){
pos[a[i]] = i;
}
auto adjust = [&](int idx){
pos[a[idx]] = idx;
};
vector <pair <int, int> > ret;
for(int i = 0 ; i < mid ; i++){
swap(a[w[i].first], a[w[i].second]);
adjust(w[i].first);
adjust(w[i].second);
if(i >= (int)c.size()) ret.emplace_back(0, 0);
else{
ret.emplace_back(pos[c[i].first], pos[c[i].second]);
swap(a[pos[c[i].first]], a[pos[c[i].second]]);
adjust(pos[c[i].first]);
adjust(pos[c[i].second]);
}
}
return ret;
}
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
n = N;
m = M;
for(int i = 0 ; i < n ; i++)
s.push_back(S[i]);
for(int i = 0 ; i < m ; i++)
w.emplace_back(X[i], Y[i]);
int l = 0, r = m;
while(l <= r){
int mid = (l + r) / 2;
auto c = check(mid);
if(c.size() == 0 || c[0].first != -1) r = mid - 1;
else l = mid + 1;
}
r++;
if(r == 0) return 0;
auto ans = check(r);
int sz = ans.size();
for(int i = 0 ; i < sz ; i++){
P[i] = ans[i].first;
Q[i] = ans[i].second;
}
return sz;
}
Compilation message
sorting.cpp: In function 'std::vector<std::pair<int, int> > swaps(std::vector<int>&)':
sorting.cpp:22:17: warning: declaration of 'i' shadows a previous local [-Wshadow]
for(int i = 1 ; i < (int)cycle.size() ; i++){
^
sorting.cpp:13:13: note: shadowed declaration is here
for(int i = 0 ; i < n ; i++){
^
sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:83:22: warning: conversion to 'int' from 'std::vector<std::pair<int, int> >::size_type {aka long unsigned int}' may alter its value [-Wconversion]
int sz = ans.size();
~~~~~~~~^~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
2 ms |
256 KB |
Output is correct |
3 |
Correct |
2 ms |
256 KB |
Output is correct |
4 |
Correct |
2 ms |
384 KB |
Output is correct |
5 |
Correct |
2 ms |
256 KB |
Output is correct |
6 |
Correct |
2 ms |
384 KB |
Output is correct |
7 |
Correct |
2 ms |
400 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
2 ms |
256 KB |
Output is correct |
3 |
Correct |
2 ms |
256 KB |
Output is correct |
4 |
Correct |
2 ms |
384 KB |
Output is correct |
5 |
Correct |
2 ms |
256 KB |
Output is correct |
6 |
Correct |
2 ms |
384 KB |
Output is correct |
7 |
Correct |
2 ms |
400 KB |
Output is correct |
8 |
Correct |
3 ms |
384 KB |
Output is correct |
9 |
Correct |
2 ms |
256 KB |
Output is correct |
10 |
Correct |
2 ms |
512 KB |
Output is correct |
11 |
Correct |
3 ms |
384 KB |
Output is correct |
12 |
Correct |
3 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
2 ms |
256 KB |
Output is correct |
3 |
Correct |
3 ms |
384 KB |
Output is correct |
4 |
Correct |
2 ms |
384 KB |
Output is correct |
5 |
Correct |
3 ms |
640 KB |
Output is correct |
6 |
Correct |
3 ms |
256 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
2 ms |
256 KB |
Output is correct |
3 |
Correct |
2 ms |
256 KB |
Output is correct |
4 |
Correct |
2 ms |
384 KB |
Output is correct |
5 |
Correct |
2 ms |
256 KB |
Output is correct |
6 |
Correct |
2 ms |
384 KB |
Output is correct |
7 |
Correct |
2 ms |
400 KB |
Output is correct |
8 |
Correct |
3 ms |
384 KB |
Output is correct |
9 |
Correct |
2 ms |
256 KB |
Output is correct |
10 |
Correct |
2 ms |
512 KB |
Output is correct |
11 |
Correct |
3 ms |
384 KB |
Output is correct |
12 |
Correct |
3 ms |
384 KB |
Output is correct |
13 |
Correct |
2 ms |
384 KB |
Output is correct |
14 |
Correct |
2 ms |
256 KB |
Output is correct |
15 |
Correct |
3 ms |
384 KB |
Output is correct |
16 |
Correct |
2 ms |
384 KB |
Output is correct |
17 |
Correct |
3 ms |
640 KB |
Output is correct |
18 |
Correct |
3 ms |
256 KB |
Output is correct |
19 |
Correct |
2 ms |
256 KB |
Output is correct |
20 |
Correct |
2 ms |
432 KB |
Output is correct |
21 |
Correct |
4 ms |
776 KB |
Output is correct |
22 |
Correct |
3 ms |
768 KB |
Output is correct |
23 |
Correct |
5 ms |
896 KB |
Output is correct |
24 |
Correct |
4 ms |
896 KB |
Output is correct |
25 |
Correct |
5 ms |
896 KB |
Output is correct |
26 |
Correct |
4 ms |
768 KB |
Output is correct |
27 |
Correct |
3 ms |
896 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
640 KB |
Output is correct |
2 |
Correct |
5 ms |
640 KB |
Output is correct |
3 |
Correct |
4 ms |
640 KB |
Output is correct |
4 |
Correct |
4 ms |
640 KB |
Output is correct |
5 |
Correct |
6 ms |
768 KB |
Output is correct |
6 |
Correct |
4 ms |
640 KB |
Output is correct |
7 |
Correct |
4 ms |
640 KB |
Output is correct |
8 |
Correct |
4 ms |
640 KB |
Output is correct |
9 |
Correct |
4 ms |
640 KB |
Output is correct |
10 |
Correct |
5 ms |
640 KB |
Output is correct |
11 |
Correct |
4 ms |
640 KB |
Output is correct |
12 |
Correct |
5 ms |
640 KB |
Output is correct |
13 |
Correct |
5 ms |
640 KB |
Output is correct |
14 |
Correct |
6 ms |
640 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
640 KB |
Output is correct |
2 |
Correct |
5 ms |
640 KB |
Output is correct |
3 |
Correct |
4 ms |
640 KB |
Output is correct |
4 |
Correct |
4 ms |
640 KB |
Output is correct |
5 |
Correct |
6 ms |
768 KB |
Output is correct |
6 |
Correct |
4 ms |
640 KB |
Output is correct |
7 |
Correct |
4 ms |
640 KB |
Output is correct |
8 |
Correct |
4 ms |
640 KB |
Output is correct |
9 |
Correct |
4 ms |
640 KB |
Output is correct |
10 |
Correct |
5 ms |
640 KB |
Output is correct |
11 |
Correct |
4 ms |
640 KB |
Output is correct |
12 |
Correct |
5 ms |
640 KB |
Output is correct |
13 |
Correct |
5 ms |
640 KB |
Output is correct |
14 |
Correct |
6 ms |
640 KB |
Output is correct |
15 |
Correct |
371 ms |
26688 KB |
Output is correct |
16 |
Correct |
542 ms |
28028 KB |
Output is correct |
17 |
Correct |
507 ms |
29392 KB |
Output is correct |
18 |
Correct |
274 ms |
28504 KB |
Output is correct |
19 |
Correct |
594 ms |
29908 KB |
Output is correct |
20 |
Correct |
543 ms |
30292 KB |
Output is correct |
21 |
Correct |
431 ms |
30420 KB |
Output is correct |
22 |
Correct |
495 ms |
23900 KB |
Output is correct |
23 |
Correct |
543 ms |
30172 KB |
Output is correct |
24 |
Correct |
530 ms |
29184 KB |
Output is correct |
25 |
Correct |
623 ms |
29752 KB |
Output is correct |
26 |
Correct |
530 ms |
28752 KB |
Output is correct |
27 |
Correct |
466 ms |
28240 KB |
Output is correct |
28 |
Correct |
575 ms |
29512 KB |
Output is correct |
29 |
Correct |
687 ms |
30152 KB |
Output is correct |
30 |
Correct |
429 ms |
28244 KB |
Output is correct |
31 |
Correct |
733 ms |
30656 KB |
Output is correct |
32 |
Correct |
474 ms |
29280 KB |
Output is correct |
33 |
Correct |
502 ms |
29784 KB |
Output is correct |
34 |
Correct |
449 ms |
30568 KB |
Output is correct |
35 |
Correct |
549 ms |
29396 KB |
Output is correct |
36 |
Correct |
240 ms |
27868 KB |
Output is correct |
37 |
Correct |
541 ms |
31312 KB |
Output is correct |
38 |
Correct |
518 ms |
30132 KB |
Output is correct |
39 |
Correct |
493 ms |
30324 KB |
Output is correct |