prog

class Solution {

public:
string s1, p1;
vector<int> removable1;
public:
    bool check(int k){
        unordered_map<int, int> mp;

        for(int i = 0;i<k;i++){
            mp[removable1[i]]=1;
        }

        string t="";
        for(int i=0;i<s1.length();i++){
            if(mp[i]){
                continue;
            }
            t+=s1[i];
        }

        int i = 0, j = 0;
        for(;i<p1.length() && j<t.length();j++){
            if(t[j]==p1[i]){
                i++;
            }
        }

        return (i == p1.length());

    }
public:
    int maximumRemovals(string s, string p, vector<int>& removable) {
        int n = removable.size(), ans = -1;
        removable1 = removable;
        s1 = s;
        p1 = p;
        int l = 0, r = n;
        while(l<=r){
            int m = (l+r)/2;
            if(check(m)){
                ans = m;
                l = m + 1;
            }else{
                r = m - 1;
            }
        }

        return ans;
    }
};