#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 7;
int n, m;
int *s, *x, *y, *p, *q;
int tmp[N], tmp2[N], where[N];
bool used[N];
int timer = 0;
int dfs(int u){
used[u] = true;
int cnt = 1;
if(!used[ tmp[u] ]){
cnt += dfs(tmp[u]);
}
return cnt;
}
void make_swap(int l, int r){
swap(tmp2[l], tmp2[r]);
swap(where[ tmp2[l] ], where[ tmp2[r] ]);
}
void dfs_ans (int u){
used[u] = true;
if(!used[ tmp[u] ]){
dfs(tmp[u]);
make_swap(x[timer], y[timer]);
p[timer] = where[tmp[u]];
q[timer] = where[u];
make_swap(p[timer], q[timer]);
++timer;
}
}
bool check(int mid){
for(int i = 0; i < n; i++){
tmp[i] = s[i];
used[i] = false;
}
for(int i = 0; i < mid; i++){
swap(tmp[ x[i] ], tmp[ y[i] ]);
}
int cnt = 0;
for(int i = 0; i < n; i++){
if(!used[i]){
cnt += dfs(i) - 1;
}
}
return (cnt <= mid);
}
void find_ans(int mid){
for(int i = 0; i < n; i++){
tmp[i] = s[i];
tmp2[i] = s[i];
where[s[i]] = i;
used[i] = false;
}
for(int i = 0; i < mid; i++){
swap(tmp[ x[i] ], tmp[ y[i] ]);
//swap(where[ s[x[i]] ], where[ s[y[i]] ]);
}
int cnt = 0;
for(int i = 0; i < n; i++){
if(!used[i]){
dfs_ans(i);
}
}
while(timer < mid){
p[timer] = 0;
q[timer++] = 0;
}
}
int findSwapPairs(int _n, int _s[], int _m, int _x[], int _y[], int _p[], int _q[]){
n = _n, s = _s, m = _m, x = _x, y = _y, p = _p, q = _q;
int l = 0, r = m;
while(l != r){
int mid = (l + r) >> 1;
if(check(mid)){
r = mid;
}
else{
l = mid + 1;
}
}
find_ans(l);
return l;
}
Compilation message
sorting.cpp: In function 'void find_ans(int)':
sorting.cpp:82:6: warning: unused variable 'cnt' [-Wunused-variable]
int cnt = 0;
^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
380 KB |
Output is correct |
2 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
3 ms |
504 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
3 ms |
504 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |