Codeforces805B. 3-palindrome 2017-05-05 08:33 156人阅读 评论(0) 收藏

B. 3-palindrome

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

In the beginning of the new year Keivan decided to reverse his name. He doesn't like palindromes, so he changed Naviek to Navick.

He is too selfish, so for a given n he wants to obtain a string of n characters,
each of which is either 'a', 'b' or 'c',
with no palindromes of length 3 appearing in the string as a substring. For
example, the strings "abc" and "abca" suit him, while
the string "aba" doesn't. He also want the number of letters 'c'
in his string to be as little as possible.

Input

The first line contains single integer n (1 ≤ n ≤ 2·105) —
the length of the string.

Output

Print the string that satisfies all the constraints.

If there are multiple answers, print any of them.

Examples

input

2

output

aa

input

3

output

bba

Note

A palindrome is a sequence of characters which reads the same backward and forward.

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题目给出一个n，要求构造出一个只含abc的字符串，要求没有长度为3的回文子串且c尽可能少

思路构造aabbaabbaabbaa这样的即可

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <vector>
using namespace std;
#define inf 0x3f3f3f3f
#define LL long long

int main()
{
    int n;
    scanf("%d",&n);
    int flag=0;
    int cnt=0;
    for(int i=1; i<=n; i++)
    {
        if(flag==0) printf("a");
        else  printf("b");
        cnt++;
        if(cnt==2)
            cnt=0,flag^=1;
    }
    printf("\n");
    return 0;
}