Problem: Nikolay got a string s of even length n, which consists only of lowercase Latin letters 'a' and 'b'. Its positions are numbered from 1 to n.

He wants to modify his string so that every its prefix of even length has an equal amount of letters 'a' and 'b'. To achieve that, Nikolay can perform the following operation arbitrary number of times (possibly, zero): choose some position in his string and replace the letter on this position with the other letter (i.e. replace 'a' with 'b' or replace 'b' with 'a'). Nikolay can use no letters except 'a' and 'b'.

The prefix of string s of length l (1 ≤ l ≤ n) is a string s[1..l].

For example, for the string s="abba" there are two prefixes of the even length. The first is s[1...2]="ab" and the second s[1...4]="abba". Both of them have the same number of 'a' and 'b'.

Your task is to calculate the minimum number of operations Nikolay has to perform with the string s to modify it so that every its prefix of even length has an equal amount of letters 'a' and 'b'.

Input

The first line of the input contains one even integer n (2 ≤ n ≤ 2⋅10^{5}) — the length of string s.

The second line of the input contains the string s of length n, which consists only of lowercase Latin letters 'a' and 'b'.

Output

In the first line print the minimum number of operations Nikolay has to perform with the string s to modify it so that every its prefix of even length has an equal amount of letters 'a' and 'b'.

In the second line print the string Nikolay obtains after applying all the operations. If there are multiple answers, you can print any of them.

Examples

Input


4
bbbb


Output


2
abba


Input


6
ababab


Output


0
ababab


Input


2
aa


Output


1
ba

Note

In the first example Nikolay has to perform two operations. For example, he can replace the first 'b' with 'a' and the last 'b' with 'a'. 

In the second example Nikolay doesn't need to do anything because each prefix of an even length of the initial string already contains an equal amount of letters 'a' and 'b'.

Solution (in JAVA):

Solution:
//  package Jobeel;
import java.util.*;
import java.io.*;
import java.lang.*;
import java.math.*;
import java.util.Map.*;

public class codeforces {
	static 	PrintWriter pw=new PrintWriter(System.out);
	static int [] size,arr;
	static String [] words;
	static long k,n,a,b,y;
	public static int find(int i) {
		if(arr[i]==i) return i;
		else {
			int result=find(arr[i]);
			arr[i]=result;
			return result;
		}
	}
public static void union(int u,int v) {
		int root_u=find(u);
		int root_v=find(v);
		if (root_u==root_v) return;
		else if(size[root_u]>size[root_v]) {
			size[root_u]+=size[root_v];
			arr[root_v]=root_u;
		}else  {
			size[root_v]+=size[root_u];
			arr[root_u]=root_v;
		}
	}
    public static long binarysearch() {
    	long low=0,high=n,ans=-1;
    	while(low<=high) {
    		long mid=(low+high)>>1;
    	    long current=mid*a+(n-mid)*b;
    	    if(current<k) { ans=Math.max(ans, mid); low=mid+1;}
    	    else high=mid-1;
    	}
    	return ans;
    }
    
    static int search(int x,pair [] arr) {
    	int low=0,high=arr.length-1,ans=-1;
    	while(low<=high) {
    		int mid=(low+high)>>1;
    	    if(arr[mid].x>=x) {ans=mid; high=mid-1;}
    	    else low=mid+1;
    	}
    	return ans;
    }
   static  int gcd(int a, int b) 
    { 
        if (b == 0) 
            return a; 
        return gcd(b, a % b);  
          
    } 
public static void main(String [] args) throws IOException, InterruptedException {
	      InputReader sc=new InputReader(System.in);
		  int x=sc.nextInt();
		  char [] ch=sc.next().toCharArray();
		  int count=0;
		  for(int i=0;i<x-1;i+=2) {
			  if(ch[i]==ch[i+1]) {
				  count++;
				  if(ch[i]=='b') ch[i]='a';
				  else ch[i]='b';
			  }
		  } 
		  pw.println(count);
		  for(char c:ch) pw.print(c);
		pw.close();
	}
	static class pair implements Comparable<pair>{
		String  name; int x,y ;
		
		
		public pair (int x,int y) {
			this.x=x; this.y=y;
		}
		public int compareTo(pair o) {
			return o.x-x;
		}
		public String toString() {
			return x+" "+y;
		}
	}

	
	static class InputReader  {
		 
		private InputStream in;
		private byte[] buffer = new byte[1024];
		private int curbuf;
		private int lenbuf;
 
		public InputReader(InputStream in) {
			this.in = in;
			this.curbuf = this.lenbuf = 0;
		}
 
		public boolean hasNextByte() {
			if (curbuf >= lenbuf) {
				curbuf = 0;
				try {
					lenbuf = in.read(buffer);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (lenbuf <= 0)
					return false;
			}
			return true;
		}
 
		private int readByte() {
			if (hasNextByte())
				return buffer[curbuf++];
			else
				return -1;
		}
 
		private boolean isSpaceChar(int c) {
			return !(c >= 33 && c <= 126);
		}
 
		private void skip() {
			while (hasNextByte() && isSpaceChar(buffer[curbuf]))
				curbuf++;
		}
 
		public boolean hasNext() {
			skip();
			return hasNextByte();
		}
 
		public String next() {
			if (!hasNext())
				throw new NoSuchElementException();
			StringBuilder sb = new StringBuilder();
			int b = readByte();
			while (!isSpaceChar(b)) {
				sb.appendCodePoint(b);
				b = readByte();
			}
			return sb.toString();
		}
 
		public int nextInt() {
			if (!hasNext())
				throw new NoSuchElementException();
			int c = readByte();
			while (isSpaceChar(c))
				c = readByte();
			boolean minus = false;
			if (c == '-') {
				minus = true;
				c = readByte();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res = res * 10 + c - '0';
				c = readByte();
			} while (!isSpaceChar(c));
			return (minus) ? -res : res;
		}
 
		public long nextLong() {
			if (!hasNext())
				throw new NoSuchElementException();
			int c = readByte();
			while (isSpaceChar(c))
				c = readByte();
			boolean minus = false;
			if (c == '-') {
				minus = true;
				c = readByte();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res = res * 10 + c - '0';
				c = readByte();
			} while (!isSpaceChar(c));
			return (minus) ? -res : res;
		}
 
		public double nextDouble() {
			return Double.parseDouble(next());
		}
 
		public int[] nextIntArray(int n) {
			int[] a = new int[n];
			for (int i = 0; i < n; i++)
				a[i] = nextInt();
			return a;
		}
 
		public long[] nextLongArray(int n) {
			long[] a = new long[n];
			for (int i = 0; i < n; i++)
				a[i] = nextLong();
			return a;
		}
 
		public char[][] nextCharMap(int n, int m) {
			char[][] map = new char[n][m];
			for (int i = 0; i < n; i++)
				map[i] = next().toCharArray();
			return map;
		}
	}

	}