FBI please teach meee. i will give you a gift then.

FBI is such a prooo. But im better :()()()()()() i am his COACH

i don't know. Please help me what they do FBI

#include <bits/stdc++.h>
using namespace std;
int main()
{
    string s;cin>>s;
    int n=s.size();
    vector<vector<int>>dp(n,vector<int>(18));
    for(int i=0;i<n;i++)
    {
        dp[i][0]=(1<<(s[i]-'a'));
    }
    for(int k=1;k<18;k++)
    {
        for(int i=0;i+(1<<k)-1<n;i++)
        {
            dp[i][k]=(dp[i][k-1]|dp[i+(1<<(k-1))][k-1]);
        }
    }
    auto get=[&](int l,int r)
    {
        int k=31-__builtin_clz(r-l+1);
        int x=(dp[l][k]|dp[r-(1<<k)+1][k]);
        return __builtin_popcount(x);
    };
    int q;cin>>q;
    while(q--)
    {
        int l,r;cin>>l>>r;
        cout<<get(l-1,r-1)<<endl;
    }
}

Never give up

You can do it

Just do it

Good luck to everyone in the div