Codeforces Round #186 (Div. 2) / 313B Ilya and Queries (字符串处理)

B. Ilya and Queries

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Ilya the Lion wants to help all his friends with passing exams. They need to solve the following problem to pass the IT exam.

You've got string s = s₁s₂... s_n (n is the length of the string), consisting only of characters "." and "#" and m queries. Each query is described by a pair of integers l_i, r_i (1 ≤ l_i < r_i ≤ n). The answer to the query l_i, r_i is the number of such integers i (l_i ≤ i < r_i), that s_i = s_i + 1.

Ilya the Lion wants to help his friends but is there anyone to help him? Help Ilya, solve the problem.

Input

The first line contains string s of length n (2 ≤ n ≤ 10⁵). It is guaranteed that the given string only consists of characters "." and "#".

The next line contains integer m (1 ≤ m ≤ 10⁵) — the number of queries. Each of the next m lines contains the description of the corresponding query. The i-th line contains integers l_i, r_i (1 ≤ l_i < r_i ≤ n).

Output

Print m integers — the answers to the queries in the order in which they are given in the input.

Sample test(s)

input

......
4
3 4
2 3
1 6
2 6

output

1
1
5
4

input

#..###
5
1 3
5 6
1 5
3 6
3 4

output

1
1
2
2
0

一遍扫描处理即可。

完整代码：

/*124ms,500KB*/

#include<cstdio>
#include<cstring>
const int maxn = 100010;

char str[maxn];
int count[maxn];

int main(void)
{
	gets(str);
	int len = strlen(str), m, l, r;
	for (int i = 1; i < len; ++i)
		count[i] = count[i - 1] + (str[i-1] == str[i]);
	scanf("%d", &m);
	while (m--)
	{
		scanf("%d%d", &l, &r);
		printf("%d\n", count[r - 1] - count[l - 1]);
	}
	return 0;
}