#include <bits/stdc++.h>
using namespace std;
template <typename T, typename U>
inline void smin(T &a, const U &b) {
  if (a > b) a = b;
}
template <typename T, typename U>
inline void smax(T &a, const U &b) {
  if (a < b) a = b;
}
template <class T>
inline void gn(T &first) {
  char c, sg = 0;
  while (c = getchar(), (c > '9' || c < '0') && c != '-')
    ;
  for ((c == '-' ? sg = 1, c = getchar() : 0), first = 0; c >= '0' && c <= '9';
       c = getchar())
    first = (first << 1) + (first << 3) + c - '0';
  if (sg) first = -first;
}
template <class T1, class T2>
inline void gn(T1 &x1, T2 &x2) {
  gn(x1), gn(x2);
}
template <class T1, class T2, class T3>
inline void gn(T1 &x1, T2 &x2, T3 &x3) {
  gn(x1, x2), gn(x3);
}
template <class T>
inline void print(T first) {
  if (first < 0) {
    putchar('-');
    return print(-first);
  }
  if (first < 10) {
    putchar('0' + first);
    return;
  }
  print(first / 10);
  putchar(first % 10 + '0');
}
template <class T>
inline void println(T first) {
  print(first);
  putchar('\n');
}
template <class T>
inline void printsp(T first) {
  print(first);
  putchar(' ');
}
template <class T1, class T2>
inline void print(T1 x1, T2 x2) {
  printsp(x1), println(x2);
}
template <class T1, class T2, class T3>
inline void print(T1 x1, T2 x2, T3 x3) {
  printsp(x1), printsp(x2), println(x3);
}
int power(int a, int b, int m, int ans = 1) {
  for (; b; b >>= 1, a = (long long)a * a % m)
    if (b & 1) ans = (long long)ans * a % m;
  return ans;
}
int p[100010], vst[100010];
vector<vector<int> > ans;
int main() {
  int n;
  gn(n);
  for (int i = 1; i <= n; i++) {
    gn(p[i]);
    if (p[i] == i) {
      puts("YES");
      for (int j = 1; j <= n; j++)
        if (i != j) {
          print(i, j);
        }
      return 0;
    }
  }
  int id = -1;
  for (int i = 1; i <= n; i++)
    if (!vst[i]) {
      int u = i;
      vector<int> v;
      while (1) {
        vst[u] = 1;
        v.push_back(u);
        u = p[u];
        if (u == i) break;
      }
      if (v.size() & 1) return puts("NO");
      ans.push_back(v);
      if (v.size() == 2) id = ans.size() - 1;
    }
  if (~id) {
    puts("YES");
    print(ans[id][0], ans[id][1]);
    for (int i = ans.size(); i--;)
      if (i != id) {
        int f = 0;
        for (int j = ans[i].size(); j--;) {
          print(ans[id][f], ans[i][j]);
          f ^= 1;
        }
      }
  } else
    puts("NO");
}
