1963

class Solution {
public:
    int minSwaps(string s) {
        int open;
        open = 0;
        int minn=0;
        for(auto c: s){
            if(c == '[') open++;
            if(c == ']') open--;
            minn = min(open, minn);
        }
        if(minn >= 0) return 0;
        minn = abs(minn);
        return (minn+1)/2;
    }
};