/*************************************
* author: marvinthang *
* created: 08.03.2023 16:53:13 *
*************************************/
#include "sorting.h"
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define left ___left
#define right ___right
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define MASK(i) (1LL << (i))
#define BIT(x, i) ((x) >> (i) & 1)
#define __builtin_popcount __builtin_popcountll
#define ALL(v) (v).begin(), (v).end()
#define REP(i, n) for (int i = 0, _n = (n); i < _n; ++i)
#define REPD(i, n) for (int i = (n); i--; )
#define FOR(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define FORD(i, b, a) for (int i = (b), _a = (a); --i >= _a; )
#define FORE(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORDE(i, b, a) for (int i = (b), _a = (a); i >= _a; --i)
#define scan_op(...) istream & operator >> (istream &in, __VA_ARGS__ &u)
#define print_op(...) ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
#include "debug.h"
#else
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define DB(...) 23
#define db(...) 23
#define debug(...) 23
#endif
template <class T> scan_op(vector <T>) { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> scan_op(pair <U, V>) { return in >> u.fi >> u.se; }
template <class U, class V> print_op(pair <U, V>) { return out << '(' << u.first << ", " << u.second << ')'; }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")"; else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
// end of template
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
auto check = [&] (int r, bool trace = false) {
vector <int> perm(S, S + N);
REP(i, r) swap(perm[X[i]], perm[Y[i]]);
vector <int> pos(N);
REP(i, N) pos[perm[i]] = i;
vector <pair <int, int>> swaps;
auto __swap = [&] (int i, int j) {
swap(perm[i], perm[j]);
swap(pos[perm[i]], pos[perm[j]]);
};
REP(i, N) {
if (perm[i] != i) {
swaps.push_back(make_pair(perm[i], i));
__swap(i, pos[i]);
}
}
if (!trace) return swaps.size() <= r;
while (swaps.size() < r) swaps.push_back(make_pair(0, 0));
copy(S, S + N, perm.begin());
REP(i, N) pos[perm[i]] = i;
REP(i, r) {
__swap(X[i], Y[i]);
P[i] = pos[swaps[i].fi];
Q[i] = pos[swaps[i].se];
__swap(P[i], Q[i]);
}
return true;
};
int l = 0, r = N;
while (l < r) {
int m = l + r >> 1;
if (check(m)) r = m;
else l = m + 1;
}
check(l, true);
return l;
}
#ifdef LOCAL
static char _buffer[1024];
static int _currentChar = 0;
static int _charsNumber = 0;
static FILE *_inputFile, *_outputFile;
static inline int _read() {
if (_charsNumber < 0) {
exit(1);
}
if (!_charsNumber || _currentChar == _charsNumber) {
_charsNumber = (int)fread(_buffer, sizeof(_buffer[0]), sizeof(_buffer), _inputFile);
_currentChar = 0;
}
if (_charsNumber <= 0) {
return -1;
}
return _buffer[_currentChar++];
}
static inline int _readInt() {
int c, x, s;
c = _read();
while (c <= 32) c = _read();
x = 0;
s = 1;
if (c == '-') {
s = -1;
c = _read();
}
while (c > 32) {
x *= 10;
x += c - '0';
c = _read();
}
if (s < 0) x = -x;
return x;
}
int main()
{
_inputFile = fopen("sorting.in", "rb");
_outputFile = fopen("sorting.out", "w");
int N, M;
N = _readInt();
int *S = (int*)malloc(sizeof(int) * (unsigned int)N);
int *perm = (int*)malloc(sizeof(int) * (unsigned int)N);
for (int i = 0; i < N; ++i)
perm[i] = S[i] = _readInt();
M = _readInt();
int *X = (int*)malloc(sizeof(int) * (unsigned int)M), *Y = (int*)malloc(sizeof(int) * (unsigned int)M);
for (int i = 0; i < M; ++i) {
X[i] = _readInt();
Y[i] = _readInt();
}
int *P = (int*)malloc(sizeof(int) * (unsigned int)M), *Q = (int*)malloc(sizeof(int) * (unsigned int)M);
int ans = findSwapPairs(N, S, M, X, Y, P, Q);
fprintf(_outputFile, "%d\n", ans);
for (int i = 0; i < ans; ++i) {
swap(perm[X[i]], perm[Y[i]]);
swap(perm[P[i]], perm[Q[i]]);
fprintf(_outputFile, "%d %d\n", P[i], Q[i]);
}
REP(i, N) fprintf(_outputFile, "%d ", perm[i]);
return 0;
}
#endif
