#include <bits/stdc++.h>
using namespace std;
int f[50005];
string s;
void nhap_tinhf()
{
getline(cin,s);
f[0]=0;
for(int i=1;i<=s.length()-1;i++)
if(s[i]=='('&&s[i-1]=='(')
f[i]=f[i-1]+1;
else
f[i]=f[i-1];
}
void giai()
{
int res=0;
for(int i=1;i<=s.length()-1;i++)
if(s[i]==')'&&s[i-1]==')')
res=res+f[i];
cout<<res;
}
int main()
{
nhap_tinhf();
giai();
}
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