#include using namespace std; typedef long long ll; typedef vector vint; typedef pair pint; typedef vector vpint; #define rep(i,n) for(int i=0;i<(n);i++) #define REP(i,n) for(int i=n-1;i>=(0);i--) #define reps(i,f,n) for(int i=(f);i<(n);i++) #define each(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++) #define all(v) (v).begin(),(v).end() #define eall(v) unique(all(v), v.end()) #define pb push_back #define mp make_pair #define fi first #define se second #define chmax(a, b) a = (((a)<(b)) ? (b) : (a)) #define chmin(a, b) a = (((a)>(b)) ? (b) : (a)) const int MOD = 1e9 + 7; const int INF = 1e9; const ll INFF = 1e18; int N, K; char s[10010]; int main(void){ scanf("%d %d", &N, &K); scanf("%s", s); for (int i = 0; i < N; ++i){ int cnt = 0; int l = min(i, K - 1); int r = max(i, K - 1); // printf("%d %d\n", l, r); if(l == r) continue; if(s[l] == '(' && s[r] == ')'){ for (int j = l; j <= r; ++j){ if(s[j] == '(')cnt++; else cnt--; } if(cnt == 0){ printf("%d\n", i + 1); break; } } } return 0; }