Description
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... sn (n is the length of the string), consisting only of characters "." and "#" and m queries. Each query is described by a pair of integers li, ri(1 ≤ li < ri ≤ n). The answer to the query li, ri is the number of such integers i(li ≤ i < ri), that si = si + 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 li, ri(1 ≤ li < ri ≤ n).
Output
Print m integers — the answers to the queries in the order in which they are given in the input.
Sample Input
...... 4 3 4 2 3 1 6 2 6
1 1 5 4
#..### 5 1 3 5 6 1 5 3 6 3 4
1 1 2 2 0
DP。
dp[i]表示到这个i位置连续出现的字符数。
那么结果便是两头一减。
#include <stdio.h>
#include <string.h>
#define N 100005
char s[N];
int dp[N];
int main()
{
int n,m;
memset(dp,0,sizeof(dp));
scanf("%s",s);
n=strlen(s);
scanf("%d",&m);
for(int i=1;i<n;i++)
{
dp[i]+=dp[i-1];
if(s[i]==s[i-1])
dp[i]++;
}
int l,r;
while(m--)
{
scanf("%d%d",&l,&r);
printf("%d\n",dp[r-1]-dp[l-1]);
}
return 0;
}