Sherlock and Subarray Queries-HackerRank

#include<bits/stdc++.h>
using namespace std;

#define pfin(a) printf("%d\n",a);
#define pfln(a) printf("%lld\n",a);
#define pfis(a) printf("%d ",a);
#define pfls(a) printf("%lld ",a);
#define sfi(a) scanf("%d",&a);
#define sfl(a) scanf("%lld",&a);
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define f(i,a,b) for(int i=a;i<b;i++)
#define pb(a) push_back(a);
#define mp(a,b) make_pair(a,b)
#define ll long long
#define F first
#define S second
#define vi vector<int>
#define vc vector<char>

const ll mod=1e9+7;
const int N=1e5+5;

int arr[N];
int n;
int table[N][17];

void build()
{
    f(i,0,n)
        table[i][0]=arr[i];

    f(j,1,17)
    {
        for(int i=0;i+(1<<j)<=n;i++)
        {
            table[i][j]=max(table[i][j-1],table[i+(1<<(j-1))][j-1]);
        }
    }

    return;
}

int query(int l,int r)
{
    int var=log2(r-l+1);

    int ans=max(table[l][var],table[r-(1<<var)+1][var]);

    return ans;
}

void solve()
{
    int m;
    sfi(n)
    sfi(m)

    vi v[N];

    f(i,0,n)
    {
        sfi(arr[i])
        v[arr[i]].pb(i)
    }

    build();

    while(m--)
    {
        int l,r;
        sfi(l)
        sfi(r)

        l--;
        r--;

        int mx=query(l,r);

        auto itr1=upper_bound(v[mx].begin(),v[mx].end(),r)-v[mx].begin();
        auto itr2=upper_bound(v[mx].begin(),v[mx].end(),l-1)-v[mx].begin();

        cout<<itr1-itr2<<endl;
    }

    return;
}

int main()
{
    solve();

    return 0;
}