# your code goes here
 
 
K = int(input())
s = input().strip()
n = len(s)
ans = 0
 
if K % 2:
    r = K // 2
    for c in range(r, n - r):
        i, j = c - r, c + r
        while i < j and s[i] == s[j]:
            i += 1
            j -= 1
        if i >= j:
            ans += 1
else:
    r = K // 2
    for c in range(r, n - r + 1):
        i, j = c - r, c + r - 1
        while i < j and s[i] == s[j]:
            i += 1
            j -= 1
        if i >= j:
            ans += 1
 
print(ans)
 

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

NQphYmFiYWI=

5
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