diff --git a/Lecture_1/extended.cpp b/Lecture_1/extended.cpp
new file mode 100644
index 0000000..c18b9fa
--- /dev/null
+++ b/Lecture_1/extended.cpp
@@ -0,0 +1,14 @@
+ll x,y;
+template<class T> T gcd(T a,T b)
+{  
+    if(a==0)
+    {
+        x=0,y=1; return b;
+    }
+    T gc=gcd(b%a,a);
+    T temp;
+    temp=x;
+    x=y-(b/a)*temp;
+    y=temp;
+    return gcd;
+}
diff --git a/Lecture_1/functors b/Lecture_1/functors
new file mode 100755
index 0000000..713f700
Binary files /dev/null and b/Lecture_1/functors differ
diff --git a/Lecture_1/functors.cpp b/Lecture_1/functors.cpp
new file mode 100644
index 0000000..b1d4677
--- /dev/null
+++ b/Lecture_1/functors.cpp
@@ -0,0 +1,151 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef long long int ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+
+
+#include<iostream>
+#include<queue>
+#include<vector>
+using namespace std;
+
+class Compare{
+public:
+	bool operator()(pair<ll,ll>  a,pair<ll,ll>  b){
+
+
+		 if(a.f<b.f)
+         return true;
+
+         if(a.f==b.f)
+         {
+             if(a.s<b.s)
+             return true;
+         }
+         return false;
+         
+	}
+
+};
+
+int main(){
+
+	//priority_queue<int> maxHeap;
+
+	priority_queue<pair<ll,ll> ,vector<pair<ll,ll> >,Compare> q; //Min Heap
+
+    ll n,i;
+    cin>>n;
+
+	vector<pair<ll,ll> > v(n);
+    FOI(i,0,n-1)
+    {
+        cin>>v[i].f;
+        cin>>v[i].s;
+    }
+	for(int i=0;i<n;i++){
+		q.push(v[i]);
+	}
+
+	//Remove
+	while(!q.empty()){
+		cout<<q.top().f<<" "<<q.top().s<<"\n";
+		q.pop();
+	}
+
+	return 0;
+}
+
+/*int main()
+{
+    ll n;
+    cin>>n;
+    ll i,x;
+    priority_queue<c,vector<c> ,    functors   > pq;
+    FOI(i,0,n-1)
+    {
+        cin>>x;
+        pq.push(x);
+    }
+
+    while(!pq.empty())
+    {
+        x=pq.top();
+        pq.pop();
+        cout<<x<<"\n";
+
+    }
+    return 0;
+}*/
+
diff --git a/Lecture_1/input.in b/Lecture_1/input.in
new file mode 100644
index 0000000..b1b7cfd
--- /dev/null
+++ b/Lecture_1/input.in
@@ -0,0 +1,2 @@
+5
+7 6 9 166 38
diff --git a/Lecture_1/output.out b/Lecture_1/output.out
new file mode 100644
index 0000000..ca6b303
--- /dev/null
+++ b/Lecture_1/output.out
@@ -0,0 +1,5 @@
+7 6
+9 166
+38 0
+ 0
+ 0
diff --git a/Lecture_1/searching b/Lecture_1/searching
new file mode 100755
index 0000000..32afadb
Binary files /dev/null and b/Lecture_1/searching differ
diff --git a/Lecture_1/searching.cpp b/Lecture_1/searching.cpp
new file mode 100644
index 0000000..f3a11ae
--- /dev/null
+++ b/Lecture_1/searching.cpp
@@ -0,0 +1,99 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef long long int ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+
+// #include<algorithm>
+int main()
+{
+    ll n,i;
+    cin>>n;
+    vector<ll> v(n);
+    FOI(i,0,n-1)
+    cin>>v[i];
+
+    ll x;
+    cin>>x;
+    if(binary_search(v.begin(),v.end(),x))
+    {
+        cout<<"found\n";
+    }
+    // lower_bound()
+
+    vector<ll>::iterator it=upper_bound(v.begin(),v.end(),x);
+    int p=(it-v.begin());
+    cout<<p<<"\n";
+
+    return 0;
+}
\ No newline at end of file
diff --git a/Lecture_1/set b/Lecture_1/set
new file mode 100755
index 0000000..8adabe6
Binary files /dev/null and b/Lecture_1/set differ
diff --git a/Lecture_1/set.cp b/Lecture_1/set.cp
new file mode 100644
index 0000000..e69de29
diff --git a/Lecture_1/set.cpp b/Lecture_1/set.cpp
new file mode 100644
index 0000000..f7587a8
--- /dev/null
+++ b/Lecture_1/set.cpp
@@ -0,0 +1,131 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef long long int ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+//#include<unorderd_map>
+
+int main()
+{
+    map<string,ll> m;
+    m["abc"]=1;
+    m["sxn"]=45;
+    m["ksk"]=3;
+
+    for(map<string,ll>::iterator it=m.begin();it!=m.end();it++)
+    {
+        cout<<it->f<<" "<<it->s<<"\n";
+    }
+    string s;
+    cin>>s;
+    map<string,ll>::iterator it=m.find(s);
+    if(it!=m.end())
+    cout<<it->s;
+    else
+    {
+        cout<<"Not found\n";
+    }
+    return 0;
+
+}
+
+// #include<set> 
+/*
+
+SET
+int main()
+{
+    ll n,i,x;
+    cin>>n;
+    set<ll> s;
+    FOI(i,0,n-1)
+    {
+        cin>>x;
+        s.insert(x);
+    }
+
+    for(set<ll>::iterator it= s.begin();it!=s.end();it++)
+    {
+        cout<<(*it)<<"\n";
+    }
+
+    cin>>x;
+    if(s.find(x)!=s.end())
+    {
+        cout<<"found\n";
+    }
+    return 0;
+
+}
+
+*/
\ No newline at end of file
diff --git a/Lecture_1/stl b/Lecture_1/stl
new file mode 100755
index 0000000..e93467a
Binary files /dev/null and b/Lecture_1/stl differ
diff --git a/Lecture_1/stl.cpp b/Lecture_1/stl.cpp
new file mode 100644
index 0000000..117ee69
--- /dev/null
+++ b/Lecture_1/stl.cpp
@@ -0,0 +1,123 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef long long int ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+bool mycompare(pair<string,ll> p1,pair<string,ll> p2)
+{
+    if(p1.f.length()<p2.f.length())
+    return true;
+
+    if(p1.f<p2.f)
+    return true;
+
+    if(p1.f==p2.f)
+    {
+        if(p1.s>p2.s)
+        return true;
+    }
+    return false;
+
+    
+}
+
+int main()
+{
+    
+    ll n,i;
+    /*char a[100];
+    cin.getline(a,100);
+    cout<<a<<"\n";
+
+    string s;
+    getline(cin,s);
+    cout<<s;*/
+    cin>>n;
+   
+    vector<pair<string,ll> >v(n);
+    FOI(i,0,n-1)
+    {
+        cin.get();
+        cin>>v[i].f;
+        cin>>v[i].s;
+        //trace(v[i].f,v[i].s);
+    }
+
+   sort(v.begin(),v.end(),mycompare);
+    FOI(i,0,n-1)
+    {
+        cout<<v[i].f<<" "<<v[i].s<<"\n";
+
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/Lecture_1/strtok b/Lecture_1/strtok
new file mode 100755
index 0000000..878d0db
Binary files /dev/null and b/Lecture_1/strtok differ
diff --git a/Lecture_1/strtok.cpp b/Lecture_1/strtok.cpp
new file mode 100644
index 0000000..e5ffb7d
--- /dev/null
+++ b/Lecture_1/strtok.cpp
@@ -0,0 +1,19 @@
+#include<iostream>
+#include<cstring>
+using namespace std;
+
+
+int main(){
+
+	char s[1000];
+	cin.getline(s,1000);
+
+	char *ptr = strtok(s," ");
+
+	while(ptr!=NULL){
+		cout<<ptr<<endl;
+		ptr = strtok(NULL," ");
+	}
+
+	return 0;
+}
\ No newline at end of file
diff --git a/Lecture_2/divisible b/Lecture_2/divisible
new file mode 100755
index 0000000..e722f0f
Binary files /dev/null and b/Lecture_2/divisible differ
diff --git a/Lecture_2/divisible.cpp b/Lecture_2/divisible.cpp
new file mode 100644
index 0000000..1f60e0b
--- /dev/null
+++ b/Lecture_2/divisible.cpp
@@ -0,0 +1,108 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef unsigned long long  ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+int main()
+{
+    ll n,i;
+    cin>>n;
+    vector<ll> v(n+1),s(n+1);
+    map<ll,vector<ll> > m;
+    m[0].pb(0);
+    FOI(i,1,n)
+    {
+        cin>>v[i];
+        s[i]=s[i-1]+v[i];
+        s[i]=s[i]%n;
+        m[s[i]].pb(i);
+    }
+    ll j;
+    FOI(i,0,n-1)
+    {
+        if(m.find(i)!=m.end())
+        {
+            if(m[i].size()>=2)
+            FOI(j,0,m[i].size()-2)
+            {
+                ll x=m[i][j]+1;
+                ll y=m[i][j+1];
+                cout<<x<<" "<<y<<"\n";
+            }
+        }
+    }
+    return 0;
+   
+
+
+}
\ No newline at end of file
diff --git a/Lecture_2/inclusion b/Lecture_2/inclusion
new file mode 100755
index 0000000..e1cc0e3
Binary files /dev/null and b/Lecture_2/inclusion differ
diff --git a/Lecture_2/inclusion.cpp b/Lecture_2/inclusion.cpp
new file mode 100644
index 0000000..e5bd687
--- /dev/null
+++ b/Lecture_2/inclusion.cpp
@@ -0,0 +1,112 @@
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace __gnu_pbds;
+using namespace std;
+
+#define pb push_back
+#define f first
+#define s second
+#define mp make_pair
+#define SZ(x) ((int)(x.size()))
+#define FOI(i, a, n) for( i = int(a); i <= int(n); i++)
+#define FOD(i, a, n) for( i = int(a); i >= int(n); i--)
+#define IN(x, y) ((y).find(x) != (y).end())
+#define ALL(t) t.begin(),t.end()
+#define MSET(tabl,i) memset(tabl, i, sizeof(tabl))
+#define PSET(x,y) fixed<<setprecision(y)<<lf(x)
+#define DBG(c) cout << #c << " = " << c << endl;
+#define RTIME ((double)clock()/(double)CLOCKS_PER_SEC)
+#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
+#define Mod 1000000007
+
+typedef unsigned long long  ll;
+typedef long double lf;
+typedef pair < ll, ll > pii;
+typedef pair < ll, ll > pll;
+typedef vector < ll > vi;
+typedef vector<vi> vvi;
+typedef complex<double> base;
+
+#define TRACE
+#ifdef TRACE
+#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
+    template <typename Arg1> 
+    void __f(const char* name, Arg1&& arg1){
+        cout << name << " : " << arg1 << std::endl;
+        //use cerr if u want to display at the bottom
+    }
+    template <typename Arg1, typename... Args>
+    void __f(const char* names, Arg1&& arg1, Args&&... args){
+        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
+    }
+#else
+#define trace(...)
+#endif
+
+const int N = 1e5 + 5;
+const int lgN = 1e6+5;
+const int te = 3e8+1;
+const ll MOD = 998244353;
+const lf pi = 3.141592653589793238462643383;
+const ll IMAX = 1e9 + 5; 
+const double PI = 3.141592653589793;
+
+
+template<class T>
+using max_pq = priority_queue<T>;
+template<class T>
+using min_pq = priority_queue<T,vector<T>,greater<T>>; 
+template<class T>
+using OST = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
+
+ll x,y;
+template<class T> T gcd(T a,T b){ if(a==0) {x=0,y=1; return b;}T gc=gcd(b%a,a);T temp;temp=x;x=y-(b/a)*temp;y=temp;return gc;}
+
+//(a^x)%m
+ll po(ll a, ll x,ll m){ if(x==0){return 1;}ll ans=1;ll k=1;  while(k<=x) {if(x&k){ans=((ans*a)%m);} k<<=1; a*=a; a%=m; }return ans; } 
+
+ll modInverse(ll A, ll M)
+{
+    gcd(A,M);
+    return (x%M+M)%M;    //x may be negative
+}
+
+int main()
+{
+    ll n,i,N;
+    cin>>n;
+    cin>>N;
+    vector<ll> v(n);
+    FOI(i,0,n-1)
+    cin>>v[i];
+    ll ans=0;
+
+    FOI(i,1,(1<<n)-1)
+    {
+        ll j=1;
+        ll temp=1;
+        ll l=0;
+        ll g=0;
+        while(j<=i)
+        {
+            if((j&i)>0)
+            {
+                temp=temp*v[l];
+                g++;
+            }
+            l++;
+            j=j<<1;
+        }
+        cout<<temp<<" temp"<<g<<"\n";
+        if(g&1)
+        ans=ans+(N/temp);
+        else
+        {
+            ans=ans-(N/temp);
+        }
+    }
+    cout<<ans<<"\n";
+    return 0;
+}
\ No newline at end of file