#include <iostream>
#include <stack>
using namespace std;
void solve(string &s){
stack<char> cur;
for(int i = 0; i < s.size(); i++){
if(!cur.empty() && ((cur.top() == '(' && s[i] == ')') || (cur.top() == '{' && s[i] == '}') || (cur.top() == '[' && s[i] == ']')))
cur.pop();
else cur.push(s[i]);
}
if(cur.empty()) cout << "YES";
else cout << "NO";
}
signed main() {
string str;
cin >> str;
solve(str);
}
begin
for i:=3 to 100 do
if i mod 3=0 then s:=s+i;
write('Сумма: ',s);
readln
end.