101501: [AtCoder]ABC150 B - Count ABC

Problem Statement

We have a string $S$ of length $N$ consisting of uppercase English letters.

How many times does ABC occur in $S$ as contiguous subsequences (see Sample Inputs and Outputs)?

Constraints

• $3 \leq N \leq 50$
• $S$ consists of uppercase English letters.

Input

Input is given from Standard Input in the following format:

$N$
$S$

Output

Print number of occurrences of ABC in $S$ as contiguous subsequences.

Sample Input 1

10
ZABCDBABCQ

Sample Output 1

2

Two contiguous subsequences of $S$ are equal to ABC: the $2$-nd through $4$-th characters, and the $7$-th through $9$-th characters.

Sample Input 2

19
THREEONEFOURONEFIVE

Sample Output 2

0

No contiguous subsequences of $S$ are equal to ABC.

Sample Input 3

33
ABCCABCBABCCABACBCBBABCBCBCBCABCB

Sample Output 3

5