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:
import java.util.*;
import java.io.*;
import java.math.*;
public class splset{
	static int mod = (int)1e9+7;
	public static PrintWriter out = new PrintWriter (new BufferedOutputStream(System.out));
	public static void main(String sp[])throws IOException{
		FastReader sc = new FastReader();
		int count=0;
		int n = sc.nextInt();
		String st = sc.next();
		StringBuilder sb =  new StringBuilder();
		for(int i=0;i<st.length();i+=2){
			int a=0;
			int b=0;
			if(st.charAt(i)=='a' && st.charAt(i+1)=='b'){
				sb.append("ab");
			}else if(st.charAt(i)=='b' && st.charAt(i+1)=='a'){
				sb.append("ba");
			}else if(st.charAt(i)=='a' && st.charAt(i+1)=='a'){
				sb.append("ab");
				count++;
			}else if(st.charAt(i)=='b' && st.charAt(i+1)=='b'){
				sb.append("ab");
				count++;
			}
		}
		System.out.println(count);
		System.out.println(sb.toString());
	
	}
	
	
	public static long calc(long num , long a, long b, long c){
		long lcmas  = (a*b)/gcd(a,b);
		long lcmbs  = (c*b)/gcd(c,b);
		long lcmcs  = (a*c)/gcd(a,c);
		long lcmll  = (lcmas*c)/gcd(c,lcmas);
		
		return (num/a)+(num/b)+(num/c)- (num/lcmas) - (num/lcmbs) - (num/lcmcs) + (num/lcmll);
		
	}
	
	
	
	
	
	//static HashMap<Integer,Integer> visited = new HashMap<>();
		
	
	/*public static int compute(int root, int n, int m, Tree[] edge, int values[]){
			
			LinkedList<Integer> ll = 	new LinkedList<>();
			ll.add(root);
				
			while(ll.size()>0){
				int val = ll.removeFirst();
				visited.put(val,0);
				ArrayList<Integer> al = edge[val].al;
				int length = al.size();
				for(int i=0;i<length;i++){
					ll.addLast(al.get(i));
					int hold = edge[val].weight+values[root];
					values[al.get(i)] = Math.min(hold,values[al.get(i)]);
				}
			}
			return values[n];
			
	}*/
	
	
	public static class Tree{
		int weight;
		int destination;
	}
	
	
	
	public static int partition(int [] arr, int s, int e){
		
		int index=s;
		int pivot = arr[e];
		for(int i=s;i<=e-1;i++){
			if(arr[i]<=pivot){
				arr = swap(arr, index, i);
				index++;
			}
		}
		swap(arr,index,e);
		print(arr);
		return index;
	}
	
	public static int[] swap(int[] arr, int low, int high){
		int temp = arr[low];
		arr[low]=arr[high];
		arr[high]=temp;
		return arr;
	}
	
	
	public static long gcd(long a, long b){
		if(b==0)
			return a;
		
		return gcd(b,a%b);
	}
	
	public static void print(int[] arr){
		for(int i=0;i<arr.length;i++)
			System.out.print(arr[i]+" ");
		System.out.println();
	}
	
	public static class pair{
		int ai;
		int bi;
	}
	
	public static class comp implements Comparator<pair>{
		public int compare(pair o1, pair o2){
			return o1.bi-o2.bi;
		}
	}
	public static class FastReader {
		BufferedReader br;
		StringTokenizer st;
	
 
		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
 
		String next() {
			while (st == null || !st.hasMoreTokens()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (Exception r) {
					r.printStackTrace();
				}
			}
			return st.nextToken();
		}
 
		int nextInt() {
			return Integer.parseInt(next());//converts string to integer
		}
 
		double nextDouble() {
			return Double.parseDouble(next());
		}
 
		long nextLong() {
			return Long.parseLong(next());
		}
 
		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (Exception r) {
				r.printStackTrace();
			}
			return str;
		}
	}
	
}