#include <cstdio>
#include <string>

/**
 * 1614. Maximum Nesting Depth of the Parentheses
 * A string is a valid parentheses string (denoted VPS) if it meets one of the following:
 * It is an empty string "", or a single character not equal to "(" or ")",
 * It can be written as AB (A concatenated with B), where A and B are VPS's, or
 * It can be written as (A), where A is a VPS.
 * We can similarly define the nesting depth depth(S) of any VPS S as follows:
 * depth("") = 0
 * depth(C) = 0, where C is a string with a single character not equal to "(" or ")".
 * depth(A + B) = max(depth(A), depth(B)), where A and B are VPS's.
 * depth("(" + A + ")") = 1 + depth(A), where A is a VPS.
 * For example, "", "()()", and "()(()())" are VPS's (with nesting depths 0, 1, and 2), and ")(" and "(()" are not VPS's.
 * Given a VPS represented as string s, return the nesting depth of s.
 */

class Solution {
public:
	static int maxDepth(const std::string& s) {
		int ret = 0, current = 0;
		for (const char* ptr = s.c_str(); *ptr; ++ptr)
			switch (*ptr) {
				case '(':
					++current;
					ret = current > ret ? current : ret;
					break;
				case ')':
					--current;
			}
		return ret;
	}
};

int main() {
	std::printf("%d\n", Solution::maxDepth("()()()(()())"));
	return 0;
}