Stones on the Table#acm刷题

Stones on the Table

CodeForces - 266A
题目：
There are n stones on the table in a row, each of them can be red, green or blue. Count the minimum number of stones to take from the table so that any two neighboring stones had different colors. Stones in a row are considered neighboring if there are no other stones between them.

Input
The first line contains integer n (1 ≤ n ≤ 50) — the number of stones on the table.

The next line contains string s, which represents the colors of the stones. We’ll consider the stones in the row numbered from 1 to n from left to right. Then the i-th character s equals “R”, if the i-th stone is red, “G”, if it’s green and “B”, if it’s blue.

Output
Print a single integer — the answer to the problem.

Examples

Input

3
RRG

Output

1

Input

5
RRRRR

Output

4

Input

4
BRBG

Output

0

• 问题简述：
  从一列三色石头中去除最小数量的石头，使得相邻石头颜色不同。
• 问题分析：
  利用字符数组循环和条件语句。产生应去除的石头的数量。
• 程序说明：
  程序主体为两个for循环，分别用于输入和计数。

c++程序代码：

#include <iostream>
using namespace std;
int main()
{
	char a[50];
	int n = 0,sum=0;
	cin >> n;
	for (int i = 0; i < n; i++)
		cin >> a[i];
	for (int i = 0; i < n - 1; i++)
	{
		if (a[i] == a[i + 1])
		{
			sum++;
		}
	}
	cout << sum << endl;
	return 0;
}