Bear and Strings

The bear has a string s = s1s2… s|s| (record |s| is the string’s length), consisting of lowercase English letters. The bear wants to count the number of such pairs of indices i, j (1 ≤ i ≤ j ≤ |s|), that string x(i, j) = sisi + 1… sj contains at least one string “bear” as a substring.

String x(i, j) contains string “bear”, if there is such index k (i ≤ k ≤ j - 3), that sk = b, sk + 1 = e, sk + 2 = a, sk + 3 = r.

Help the bear cope with the given problem.

Input
The first line contains a non-empty string s (1 ≤ |s| ≤ 5000). It is guaranteed that the string only consists of lowercase English letters.

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

Examples
Input
bearbtear
Output
6
Input
bearaabearc
Output
20
Note
In the first sample, the following pairs (i, j) match: (1, 4), (1, 5), (1, 6), (1, 7), (1, 8), (1, 9).

In the second sample, the following pairs (i, j) match: (1,  4), (1,  5), (1,  6), (1,  7), (1,  8), (1,  9), (1,  10), (1,  11), (2,  10), (2,  11), (3,  10), (3,  11), (4,  10), (4,  11), (5,  10), (5,  11), (6,  10), (6,  11), (7,  10), (7,  11).

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char *argv[]) {
	char s[5100];
	scanf("%s",&s);
	int i,j;
	int len=strlen(s);
	if(len<4)
	printf("0");
	else{
		int count=0;
		for(i=0;i<len-3;i++){
			for(j=i;j<len-3;j++){
					if(s[j]=='b'&&s[j+1]=='e'&&s[j+2]=='a'&&s[j+3]=='r')
					{	
						count+=(len-3-j);
						break;
					}
			}
		}
		printf("%d\n",count);
		
	}
	
	return 0;
}
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