Check if a Parentheses String Can Be Valid.java

class Solution {
    public boolean canBeValid(String s, String locked) {
        int n = s.length();
        if (n % 2 != 0) return false;
        
        int possibleOpens = 0;
        int fixedCloses = 0;
        
        for (int i = 0; i < n; i ++) {
            if (s.charAt(i) == '(' || locked.charAt(i) == '0') {
                possibleOpens++;
            } else {
                fixedCloses++;
            }
            
            if (fixedCloses > possibleOpens) return false;
        }
        
        int possibleCloses = 0;
        int fixedOpens = 0;
        
        for (int i = n - 1; i >= 0; i--) {
            if (s.charAt(i) == ')' || locked.charAt(i) == '0') {
                possibleCloses++;
            } else {
                fixedOpens++;
            }
            
            if (fixedOpens > possibleCloses) return false;
        }
        
        return true;
    }
}