#pragma GCC optimize ("O3") #include "bits/stdc++.h" using namespace std; using ll = long long int; #define debug(v) {printf("L%d %s > ",__LINE__,#v);cout<<(v)< ",__LINE__,#v);for(auto e:(v)){cout< ",__LINE__,#m);for(int x=0;x<(w);x++){cout<<(m)[x]<<" ";}cout<\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[y][x]<<" ";}cout<::type cnt=0;(cnt)<(l);++(cnt)) #define rrepeat(cnt,l) for(auto cnt=(l)-1;0<=(cnt);--(cnt)) #define iterate(cnt,b,e) for(auto cnt=(b);(cnt)!=(e);++(cnt)) #define diterate(cnt,b,e) for(auto cnt=(b);(cnt)!=(e);--(cnt)) const ll MD = 1000000007ll; const long double PI = 3.1415926535897932384626433832795L; inline void assert_call(bool assertion, function f) { if (!assertion) { cerr << "assertion fault:" << endl; f(); abort(); } } template inline ostream& operator <<(ostream &o, const pair p) { o << '(' << p.first << ':' << p.second << ')'; return o; } template inline ostream& _ostream_vecprint(ostream &o, const Vec& p) { o << '['; for (auto& e : p) o << e << ','; o << ']'; return o; } template inline ostream& operator<<(ostream& o, const vector& v) { return _ostream_vecprint(o, v); } template inline ostream& operator<<(ostream& o, const array& v) { return _ostream_vecprint(o, v); } template inline T& maxset(T& to, const T& val) { return to = max(to, val); } template inline T& minset(T& to, const T& val) { return to = min(to, val); } void bye(string s, int code = 0) { cout << s << endl; exit(code); } mt19937_64 randdev(8901016); template inline T rand(T l, T h) { return uniform_int_distribution(l, h)(randdev); } template<> inline double rand(double l, double h) { return uniform_real_distribution(l, h)(randdev); } template<> inline float rand(float l, float h) { return uniform_real_distribution(l, h)(randdev); } #if defined(_WIN32) || defined(_WIN64) #define getchar_unlocked _getchar_nolock #define putchar_unlocked _putchar_nolock #elif defined(__GNUC__) #else #define getchar_unlocked getchar #define putchar_unlocked putchar #endif namespace { #define isvisiblechar(c) (0x21<=(c)&&(c)<=0x7E) class MaiScanner { public: template void input_integer(T& var) { var = 0; T sign = 1; int cc = getchar_unlocked(); for (; cc<'0' || '9'>(int& var) { input_integer(var); return *this; } inline MaiScanner& operator>>(long long& var) { input_integer(var); return *this; } inline MaiScanner& operator>>(string& var) { int cc = getchar_unlocked(); for (; !isvisiblechar(cc); cc = getchar_unlocked()); for (; isvisiblechar(cc); cc = getchar_unlocked()) var.push_back(cc); return *this; } template void in(IT begin, IT end) { for (auto it = begin; it != end; ++it) *this >> *it; } }; class MaiPrinter { public: template void output_integer(T var) { if (var == 0) { putchar_unlocked('0'); return; } if (var < 0) putchar_unlocked('-'), var = -var; char stack[32]; int stack_p = 0; while (var) stack[stack_p++] = '0' + (var % 10), var /= 10; while (stack_p) putchar_unlocked(stack[--stack_p]); } inline MaiPrinter& operator<<(char c) { putchar_unlocked(c); return *this; } inline MaiPrinter& operator<<(int var) { output_integer(var); return *this; } inline MaiPrinter& operator<<(long long var) { output_integer(var); return *this; } inline MaiPrinter& operator<<(char* str_p) { while (*str_p) putchar_unlocked(*(str_p++)); return *this; } inline MaiPrinter& operator<<(const string& str) { const char* p = str.c_str(); const char* l = p + str.size(); while (p < l) putchar_unlocked(*p++); return *this; } template void join(IT begin, IT end, char sep = ' ') { for (bool b = 0; begin != end; ++begin, b = 1) b ? *this << sep << *begin : *this << *begin; } }; } MaiScanner scanner; MaiPrinter printer; ll N; string str; vector> pairs; // int main() { scanner >> N >> str; assert(N == str.size()); pairs.reserve(N + 1); pairs.push_back({0, 0, 0, 0}); repeat(i, N) { ll sum = (str[i] == '(' ? 1 : -1) + pairs.back()[2]; ll smallest = min(pairs.back()[1], sum); pairs.push_back({0, smallest, sum, ll(i+1)}); } sort(ALL(pairs), greater()); ll ans = 0; // offset = 使っていない"("の数 ll o = 0; for (auto p : pairs) { //cout << p << endl; // smallest,sum,size ll sm,su,sz; sm = p[1], su = p[2], sz = p[3]; if (sz == 0) continue; // 直前までの連結済み文字列によって増える:min(o, -sm)*2 // 今注目している文字列のみによって増える:sz-su+sm*2 // 今注目している文字列のみについて,使っていない"("の数:max(0,su-sm) // 消費した直前の"(":min(o,-sm) // 余っている"("の数の合計:o-min(o,-sm)+max(0,su-sm) ans += sz - su + sm*2 + min(o, -sm)*2; o = (o-min(o, -sm))+max(0ll, su-sm); } cout << ans << endl; return 0; }