package contest220325; import java.io.*; import java.util.*; import java.util.function.Consumer; import java.util.function.IntUnaryOperator; import java.util.function.LongUnaryOperator; public class F { InputStream is; FastWriter out; String INPUT = ""; public void solve() { int n = ni(); int[] a = na(n); int[] parity = new int[n+1]; int[] ft = new int[n+5]; for(int i = 0;i < n;i++){ parity[a[i]] = sumFenwick(ft, a[i]) % 2; addFenwick(ft, a[i], 1); } Node[] nodes = new Node[n+1]; Node root = null; for(int i = 0;i < n;i++){ nodes[a[i]] = new Node(parity[a[i]], a[i]); root = merge(root, nodes[a[i]]); } Deque route = new ArrayDeque<>(); for(int i = n;i >= 1;i--){ Node tar = nodes[i]; int ind = index(tar); root = delete(root, ind); if(ind % 2 == 1){ if(sum(root) == size(root)){ out.println("No"); return; } Node lazy = null; Node cur = root; while(cur != null){ if(sum(cur.R) < size(cur.R)){ cur = cur.R; }else if(cur.v == 0){ lazy = cur; break; }else{ cur = cur.L; } } assert lazy != null; if(index(lazy) % 2 != 0){ out.println("No"); return; } int pos = index(lazy); root = delete(root, pos); route.addFirst("" + lazy.id + " " + (pos+1)); route.addFirst("" + i + " " + (ind)); i--; while(i > lazy.id){ ind = index(nodes[i]); root = delete(root, ind); route.addFirst("" + i + " " + (ind+1)); i--; } }else{ route.addFirst("" + i + " " + (ind+1)); } } out.println("Yes"); for(String r : route){ out.println(r); } } public static Random gen = new Random(); public static final int mod = 998244353; static public class Node { public long priority; public Node L, R, P; int id; public long v; // value public long sum; public int size; public Node(int v, int id) { this.v = v; this.id = id; priority = gen.nextLong(); update(); } public void update() { size = size(L) + size(R) + 1; sum = v + sum(L) + sum(R); // TODO } @Override public String toString() { return "Node{" + "v=" + v + ", sum=" + sum + ", size=" + size + '}'; } } public static void propagate(Node x) { for(;x != null;x = x.P)x.update(); } public static Node disconnect(Node a) { if(a == null)return null; a.L = a.R = a.P = null; a.update(); return a; } public static int size(Node x){ return x == null ? 0 : x.size;} public static long sum(Node x){ return x == null ? 0 : x.sum;} public static void setParent(Node a, Node par) { if(a != null)a.P = par; } public static Node merge(Node a, Node b, Node... c) { Node x = merge(a, b); for(Node n : c)x = merge(x, n); return x; } public static Node merge(Node a, Node b) { if(b == null)return a; if(a == null)return b; if(a.priority > b.priority){ setParent(a.R, null); setParent(b, null); a.R = merge(a.R, b); setParent(a.R, a); a.update(); return a; }else{ setParent(a, null); setParent(b.L, null); b.L = merge(a, b.L); setParent(b.L, b); b.update(); return b; } } public static Node[] split(Node x) { if(x == null)return new Node[]{null, null}; if(x.L != null)x.L.P = null; Node[] sp = new Node[]{x.L, x}; x.L = null; x.update(); while(x.P != null){ Node p = x.P; x.P = null; if(x == p.L){ p.L = sp[1]; if(sp[1] != null)sp[1].P = p; sp[1] = p; }else{ p.R = sp[0]; if(sp[0] != null)sp[0].P = p; sp[0] = p; } p.update(); x = p; } return sp; } // [0,K),[K,N) public static Node[] split(Node a, int K) { if(a == null)return new Node[]{null, null}; if(K <= size(a.L)){ setParent(a.L, null); Node[] s = split(a.L, K); a.L = s[1]; setParent(a.L, a); a.update(); s[1] = a; return s; }else{ setParent(a.R, null); Node[] s = split(a.R, K- size(a.L)-1); a.R = s[0]; setParent(a.R, a); a.update(); s[0] = a; return s; } } public static Node insertb(Node root, Node x) { assert x != null; int ind = lowerBound(root, x.v); return insert(root, ind, x); } public static Node insert(Node root, int K, Node x) { assert K >= 0; assert K <= size(root); assert size(x) == 1; Node[] sp = split(root, K); return merge(sp[0], x, sp[1]); } public static Node delete(Node root, int K) { assert K >= 0; assert K < size(root); Node[] lm_r = split(root, K+1); Node[] l_m = split(lm_r[0], K); return merge(l_m[0], lm_r[1]); } public static Node get(Node a, int K) { assert K >= 0; assert K < size(a); while(a != null){ if(K < size(a.L)){ a = a.L; }else if(K == size(a.L)){ break; }else{ K = K - size(a.L)-1; a = a.R; } } return a; } public static int index(Node a) { assert a != null; int ind = size(a.L); while(a != null){ Node par = a.P; if(par != null && par.R == a){ ind += size(par.L) + 1; } a = par; } return ind; } public static Node mergeTechnically(Node x, Node y) { if(size(x) > size(y)){ Node d = x; x = y; y = d; } // |x|<=|y| for(Node cur : nodesdfs(x))y = insertb(y, disconnect(cur)); return y; } public static int lowerBound(Node a, long q) { int lcount = 0; while(a != null){ if(a.v >= q){ a = a.L; }else{ lcount += size(a.L) + 1; a = a.R; } } return lcount; } public static Node next(Node x) { if(x == null)return null; if(x.R != null){ x = x.R; while(x.L != null)x = x.L; return x; }else{ while(true){ Node p = x.P; if(p == null)return null; if(p.L == x)return p; x = p; } } } public static Node prev(Node x) { if(x == null)return null; if(x.L != null){ x = x.L; while(x.R != null)x = x.R; return x; }else{ while(true){ Node p = x.P; if(p == null)return null; if(p.R == x)return p; x = p; } } } public static Node build(Node[] a){return build(a, 0, a.length);} public static Node build(Node[] a, int l, int r) { if(l >= r)return null; int h = l+r>>1; Node root = a[h]; Node L = build(a, l, h); root.L = L; if(L != null)L.P = root; Node R = build(a, h+1, r); root.R = R; if(R != null)R.P = root; root.update(); return root; } public static Node[] nodes(Node a) { return nodes(a, new Node[size(a)], 0, size(a)); } public static Node[] nodes(Node a, Node[] ns, int L, int R) { if(a == null)return ns; nodes(a.L, ns, L, L+ size(a.L)); ns[L+ size(a.L)] = a; nodes(a.R, ns, R- size(a.R), R); return ns; } // faster than nodes but inconsistent public static Node[] nodesdfs(Node a) { return nodesdfs(a, new Node[a.size], new int[]{0}); } public static Node[] nodesdfs(Node a, Node[] ns, int[] pos) { if(a == null)return ns; ns[pos[0]++] = a; nodesdfs(a.L, ns, pos); nodesdfs(a.R, ns, pos); return ns; } public static String toString(Node a, String indent) { if(a == null)return ""; return toString(a.L, indent + " ") + indent + a + "\n" + toString(a.R, indent + " "); } public static Node operate(Node root, int l, int r, Consumer o) { Node[] lm_r = split(root, r); Node[] l_m = split(lm_r[0], l); o.accept(l_m[1]); l_m[1].update(); return merge(l_m[0], l_m[1], lm_r[1]); } public static int sumFenwick(int[] ft, int i) { int sum = 0; for(i++;i > 0;i -= i&-i)sum += ft[i]; return sum; } public static void addFenwick(int[] ft, int i, int v) { if(v == 0 || i < 0)return; int n = ft.length; for(i++;i < n;i += i&-i)ft[i] += v; } public static int firstGEFenwick(int[] ft, int v) { int i = 0, n = ft.length; for(int b = Integer.highestOneBit(n);b != 0;b >>= 1){ if((i|b) < n && ft[i|b] < v){ i |= b; v -= ft[i]; } } return i; } public static void main(String[] args) { new F().run(); } public void run() { long S = System.currentTimeMillis(); is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes()); out = new FastWriter(System.out); solve(); out.flush(); long G = System.currentTimeMillis(); tr(G-S+"ms"); // Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){ // @Override // public void run() { // long s = System.currentTimeMillis(); // solve(); // out.flush(); // if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms"); // } // }; // t.start(); // t.join(); } private boolean eof() { if(lenbuf == -1)return true; int lptr = ptrbuf; while(lptr < lenbuf)if(!isSpaceChar(inbuf[lptr++]))return false; try { is.mark(1000); while(true){ int b = is.read(); if(b == -1){ is.reset(); return true; }else if(!isSpaceChar(b)){ is.reset(); return false; } } } catch (IOException e) { return true; } } private final byte[] inbuf = new byte[1024]; public int lenbuf = 0, ptrbuf = 0; private int readByte() { if(lenbuf == -1)throw new InputMismatchException(); if(ptrbuf >= lenbuf){ ptrbuf = 0; try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); } if(lenbuf <= 0)return -1; } return inbuf[ptrbuf++]; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } // private boolean isSpaceChar(int c) { return !(c >= 32 && c <= 126); } private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; } private double nd() { return Double.parseDouble(ns()); } private char nc() { return (char)skip(); } private String ns() { int b = skip(); StringBuilder sb = new StringBuilder(); while(!(isSpaceChar(b))){ sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } private char[] ns(int n) { char[] buf = new char[n]; int b = skip(), p = 0; while(p < n && !(isSpaceChar(b))){ buf[p++] = (char)b; b = readByte(); } return n == p ? buf : Arrays.copyOf(buf, p); } private char[][] nm(int n, int m) { char[][] map = new char[n][]; for(int i = 0;i < n;i++)map[i] = ns(m); return map; } private int[] na(int n) { int[] a = new int[n]; for(int i = 0;i < n;i++)a[i] = ni(); return a; } private long[] nal(int n) { long[] a = new long[n]; for(int i = 0;i < n;i++)a[i] = nl(); return a; } private int ni() { int num = 0, b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } private long nl() { long num = 0; int b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } public static class FastWriter { private static final int BUF_SIZE = 1<<13; private final byte[] buf = new byte[BUF_SIZE]; private final OutputStream out; private int ptr = 0; private FastWriter(){out = null;} public FastWriter(OutputStream os) { this.out = os; } public FastWriter(String path) { try { this.out = new FileOutputStream(path); } catch (FileNotFoundException e) { throw new RuntimeException("FastWriter"); } } public FastWriter write(byte b) { buf[ptr++] = b; if(ptr == BUF_SIZE)innerflush(); return this; } public FastWriter write(char c) { return write((byte)c); } public FastWriter write(char[] s) { for(char c : s){ buf[ptr++] = (byte)c; if(ptr == BUF_SIZE)innerflush(); } return this; } public FastWriter write(String s) { s.chars().forEach(c -> { buf[ptr++] = (byte)c; if(ptr == BUF_SIZE)innerflush(); }); return this; } private static int countDigits(int l) { if (l >= 1000000000) return 10; if (l >= 100000000) return 9; if (l >= 10000000) return 8; if (l >= 1000000) return 7; if (l >= 100000) return 6; if (l >= 10000) return 5; if (l >= 1000) return 4; if (l >= 100) return 3; if (l >= 10) return 2; return 1; } public FastWriter write(int x) { if(x == Integer.MIN_VALUE){ return write((long)x); } if(ptr + 12 >= BUF_SIZE)innerflush(); if(x < 0){ write((byte)'-'); x = -x; } int d = countDigits(x); for(int i = ptr + d - 1;i >= ptr;i--){ buf[i] = (byte)('0'+x%10); x /= 10; } ptr += d; return this; } private static int countDigits(long l) { if (l >= 1000000000000000000L) return 19; if (l >= 100000000000000000L) return 18; if (l >= 10000000000000000L) return 17; if (l >= 1000000000000000L) return 16; if (l >= 100000000000000L) return 15; if (l >= 10000000000000L) return 14; if (l >= 1000000000000L) return 13; if (l >= 100000000000L) return 12; if (l >= 10000000000L) return 11; if (l >= 1000000000L) return 10; if (l >= 100000000L) return 9; if (l >= 10000000L) return 8; if (l >= 1000000L) return 7; if (l >= 100000L) return 6; if (l >= 10000L) return 5; if (l >= 1000L) return 4; if (l >= 100L) return 3; if (l >= 10L) return 2; return 1; } public FastWriter write(long x) { if(x == Long.MIN_VALUE){ return write("" + x); } if(ptr + 21 >= BUF_SIZE)innerflush(); if(x < 0){ write((byte)'-'); x = -x; } int d = countDigits(x); for(int i = ptr + d - 1;i >= ptr;i--){ buf[i] = (byte)('0'+x%10); x /= 10; } ptr += d; return this; } public FastWriter write(double x, int precision) { if(x < 0){ write('-'); x = -x; } x += Math.pow(10, -precision)/2; // if(x < 0){ x = 0; } write((long)x).write("."); x -= (long)x; for(int i = 0;i < precision;i++){ x *= 10; write((char)('0'+(int)x)); x -= (int)x; } return this; } public FastWriter writeln(char c){ return write(c).writeln(); } public FastWriter writeln(int x){ return write(x).writeln(); } public FastWriter writeln(long x){ return write(x).writeln(); } public FastWriter writeln(double x, int precision){ return write(x, precision).writeln(); } public FastWriter write(int... xs) { boolean first = true; for(int x : xs) { if (!first) write(' '); first = false; write(x); } return this; } public FastWriter write(long... xs) { boolean first = true; for(long x : xs) { if (!first) write(' '); first = false; write(x); } return this; } public FastWriter write(IntUnaryOperator f, int... xs) { boolean first = true; for(int x : xs) { if (!first) write(' '); first = false; write(f.applyAsInt(x)); } return this; } public FastWriter write(LongUnaryOperator f, long... xs) { boolean first = true; for(long x : xs) { if (!first) write(' '); first = false; write(f.applyAsLong(x)); } return this; } public FastWriter writeln() { return write((byte)'\n'); } public FastWriter writeln(int... xs) { return write(xs).writeln(); } public FastWriter writeln(long... xs) { return write(xs).writeln(); } public FastWriter writeln(IntUnaryOperator f, int... xs) { return write(f, xs).writeln(); } public FastWriter writeln(LongUnaryOperator f, long... xs) { return write(f, xs).writeln(); } public FastWriter writeln(char[] line) { return write(line).writeln(); } public FastWriter writeln(char[]... map) { for(char[] line : map)write(line).writeln();return this; } public FastWriter writeln(String s) { return write(s).writeln(); } private void innerflush() { try { out.write(buf, 0, ptr); ptr = 0; } catch (IOException e) { throw new RuntimeException("innerflush"); } } public void flush() { innerflush(); try { out.flush(); } catch (IOException e) { throw new RuntimeException("flush"); } } public FastWriter print(byte b) { return write(b); } public FastWriter print(char c) { return write(c); } public FastWriter print(char[] s) { return write(s); } public FastWriter print(String s) { return write(s); } public FastWriter print(int x) { return write(x); } public FastWriter print(long x) { return write(x); } public FastWriter print(double x, int precision) { return write(x, precision); } public FastWriter println(char c){ return writeln(c); } public FastWriter println(int x){ return writeln(x); } public FastWriter println(long x){ return writeln(x); } public FastWriter println(double x, int precision){ return writeln(x, precision); } public FastWriter print(int... xs) { return write(xs); } public FastWriter print(long... xs) { return write(xs); } public FastWriter print(IntUnaryOperator f, int... xs) { return write(f, xs); } public FastWriter print(LongUnaryOperator f, long... xs) { return write(f, xs); } public FastWriter println(int... xs) { return writeln(xs); } public FastWriter println(long... xs) { return writeln(xs); } public FastWriter println(IntUnaryOperator f, int... xs) { return writeln(f, xs); } public FastWriter println(LongUnaryOperator f, long... xs) { return writeln(f, xs); } public FastWriter println(char[] line) { return writeln(line); } public FastWriter println(char[]... map) { return writeln(map); } public FastWriter println(String s) { return writeln(s); } public FastWriter println() { return writeln(); } } public static void trnz(int... o) { for(int i = 0;i < o.length;i++)if(o[i] != 0)System.out.print(i+":"+o[i]+" "); System.out.println(); } // print ids which are 1 public static void trt(long... o) { Queue stands = new ArrayDeque<>(); for(int i = 0;i < o.length;i++){ for(long x = o[i];x != 0;x &= x-1)stands.add(i<<6|Long.numberOfTrailingZeros(x)); } System.out.println(stands); } public static void tf(boolean... r) { for(boolean x : r)System.out.print(x?'#':'.'); System.out.println(); } public static void tf(boolean[]... b) { for(boolean[] r : b) { for(boolean x : r)System.out.print(x?'#':'.'); System.out.println(); } System.out.println(); } public void tf(long[]... b) { if(INPUT.length() != 0) { for (long[] r : b) { for (long x : r) { for (int i = 0; i < 64; i++) { System.out.print(x << ~i < 0 ? '#' : '.'); } } System.out.println(); } System.out.println(); } } public void tf(long... b) { if(INPUT.length() != 0) { for (long x : b) { for (int i = 0; i < 64; i++) { System.out.print(x << ~i < 0 ? '#' : '.'); } } System.out.println(); } } private void tr(Object... o) { if(INPUT.length() != 0)System.out.println(Arrays.deepToString(o)); } }