Class - 22 : Task - 1

#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
typedef tree< double, null_type, less_equal<double>, rb_tree_tag, tree_order_statistics_node_update > ordered_set;
const int mx=2e5+123;
long long sum0[mx],sum1[mx];
int main()
{
    int q;
    cin>>q;
    for(int j=1;j<=q;j++)
    {
        string s;
        int k;
        ordered_set ps;
        cin>>s>>k;
        sum0[0]=0;
        sum1[0]=0;
        for(int i=0;i<s.size();i++)
        {
            if(s[i]=='0')
            {
                sum0[i+1]=sum0[i]+1;
                sum1[i+1]=sum1[i];
            }
            else
            {
                sum1[i+1]=sum1[i]+1;
                sum0[i+1]=sum0[i];
            }


        }
        long long ans=0;
        ps.insert(0);
        map<long long, int>cnt;
        cnt[0]++;
        for(int i=1;i<=s.size();i++)
        {

           ans+=ps.order_of_key(sum0[i]-(k*sum1[i]))+cnt[sum0[i]-(k*sum1[i])];
           cnt[sum0[i]-(k*sum1[i])]++;
           ps.insert(sum0[i]-(k*sum1[i]));


        }
        cout<<ans;


    }
}