int find(string s){
    int total = 1, o = 0, z = 1;
    bool flag = 1;
    for(auto i: s){
        if(i == '0'){
            flag = 0;
            int save = total;
            total = 2 * total - z;
            z += save - z;
        }
        else{
            int save = total;
            total = 2 * total - o;
            o += save - o;
        }
    }
    return total - flag;
}