#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define ld long double
#define inf 0x3f3f3f3f
#define endl '\n'

int n,maxn;
bool y=1;
string s;
int dp[3000007];

int main(){
	freopen("bracket.in","r",stdin);
	freopen("bracket.out","w",stdout);
	
	cin>>s;
	n=s.size();
	s=" "+s;
	
	for(int i=1;i<=n;i++){
		if(s[i]=='(') dp[i]=dp[i-1]+1;
		else dp[i]=dp[i-1]-1;
		maxn=max(maxn,dp[i]);
		if(dp[i]<0){
			y=0;
			break;
		}
	}
	if(!(y&&dp[n]==0)){
		cout<<-1;
		return 0;
	}
	
	cout<<n-maxn*2;

	return 0;
}