//#include "sorting.h"
#include <bits/stdc++.h>
using namespace std;
const int mxN = (int)2e5+10;
int n, tot, a[mxN], t[mxN], x[mxN], y[mxN], p[mxN], vis[mxN];
int chk(int m, int P[], int Q[]){
for(int i = 0; i < n; i++) a[i] = t[i], vis[i]=0;
for(int i = 0; i < m; i++) swap(a[x[i]],a[y[i]]), P[i]=Q[i]=0;
for(int i = 0; i < n; i++) p[a[i]]=i;
tot = 0; fill(vis,vis+n,0);
for(int i = 0; i < n; i++){
if(vis[i]) continue;
int j = i; vector<int> v; v.clear();
while(!vis[j]){
vis[j] = 1; if(vis[p[j]]) break;
P[tot]=j,Q[tot++]=p[j], j = p[j];
}
}
return (tot<=m)?m:mxN;
}
int findSwapPairs(int N, int A[], int m, int X[], int Y[], int P[], int Q[]) {
n = N;
if(is_sorted(A,A+n)) return 0;
for(int i = 0; i < n; i++){
a[i] = t[i] = A[i];
x[i] = X[i], y[i] = Y[i];
}
int l = 0, r = n;
while(l<r){
int mid = (l+r)/2;
if(chk(mid,P,Q)<=mid) r=mid;
else l=mid+1;
}
m = l;
for(int i = 0; i < n; i++) a[i] = t[i], vis[i]=0;
for(int i = 0; i < m; i++) swap(a[x[i]],a[y[i]]), P[i]=Q[i]=0;
for(int i = 0; i < n; i++) p[a[i]]=i;
tot = 0; fill(vis,vis+n,0);
for(int i = 0; i < n; i++){
if(vis[i]) continue;
int j = i; vector<int> v; v.clear();
while(!vis[j]){
vis[j] = 1; if(vis[p[j]]) break;
P[tot]=j,Q[tot++]=p[j], j = p[j];
}
}
return l;
}
