Codeforces Round #258 (Div. 2) D. Count Good Substrings

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本文介绍了一种统计字符串中特定模式的好子串数量的方法。通过输入一个由字符'a'和'b'组成的字符串，算法能够计算出所有可能子串中，奇数长度和偶数长度的好子串的数量。好子串定义为在连续相同字符合并后的回文子串。

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We call a string good, if after merging all the consecutive equal characters, the resulting string is palindrome. For example, "aabba" is good, because after the merging step it will become "aba".

Given a string, you have to find two values:

the number of good substrings of even length;
the number of good substrings of odd length.

Input

The first line of the input contains a single string of length n (1 ≤ n ≤ 10⁵). Each character of the string will be either 'a' or 'b'.

Output

Print two space-separated integers: the number of good substrings of even length and the number of good substrings of odd length.

Examples

Input

bb

Output

1 2

Input

baab

Output

2 4

Input

babb

Output

2 5

Input

babaa

Output

2 7

Note

In example 1, there are three good substrings ("b", "b", and "bb"). One of them has even length and two of them have odd length.

In example 2, there are six good substrings (i.e. "b", "a", "a", "b", "aa", "baab"). Two of them have even length and four of them have odd length.

In example 3, there are seven good substrings (i.e. "b", "a", "b", "b", "bb", "bab", "babb"). Two of them have even length and five of them have odd length.

Definitions

A substring s[l, r] (1 ≤ l ≤ r ≤ n) of string s = s₁s₂... s_n is string s_ls_l + 1... s_r.

A string s = s₁s₂... s_n is a palindrome if it is equal to string s_ns_n - 1... s₁.

题解：统计奇偶位置a b的个数，然后完了。。。

#include <cstdio>
#include <cstring>
#include <iostream>
#define got(x) (x)*(x+1)/2
using namespace std;
string s;
long long num[2][2];
using namespace std;
int main()
{
	cin.sync_with_stdio(false);
	cin>>s;
	int n = s.length(); 
	for(int i = 0;i < n;i++) num[i%2][s[i]-'a']++;
	cout<<num[0][1]*num[1][1] + num[0][0]*num[1][0]<<" "; 
	cout<<got(num[0][0]) + got(num[0][1]) + got(num[1][0]) + got(num[1][1]);
}