n,k = map(int ,input().split())
s = list(input())
k -= 1
f = 0
if s[k] == '(':
    s = [ str(i) if j == ')' else j for i,j in enumerate(s,1)]
    s[k] = 'A'
    for j in range(n//2):
        for i in range(len(s)):
            if s[i] == '(' and str.isdecimal(s[i+1]):
                s.pop(i)
                s.pop(i)
                break
            elif s[i] == 'A' and str.isdecimal(s[i+1]):
                f = s[i+1]
                break
        else:
            continue
        if f != 0:
            break
    print(f)
else:
    s = [ str(i) if j == '(' else j for i,j in enumerate(s,1) ]
    s[k] = 'A'
    for j in range(n//2):
        for i in range(len(s)):
            if s[i+1] == ')' and str.isdecimal(s[i]):
                s.pop(i)
                s.pop(i)
                break
            elif s[i+1] == 'A' and str.isdecimal(s[i]):
                f = s[i]
                break
        else:
            continue
        if f != 0:
            break
    print(f)