Kasihymiö

input/code.cpp: In function 'int main()':
input/code.cpp:10:33: error: expected primary-expression before '=' token
  for (int i = s.length()-1; i > =0; i--){
                                 ^

#include <iostream>
#include <cstring>
#include <string>
using namespace std;
int main(){
	int c = 0;
	int p = 0;
	string s;
	cin >> s;
	for (int i = s.length()-1; i > =0; i--){
		if(s.substr(i, 1).compare(")") == 0){
			p = p + 1;
		} else {
			c = c + p;
		}
	}
	cout << c << endl;
}