diff --git a/algorithms/CPlusPlus/.gitignore b/algorithms/CPlusPlus/.gitignore
new file mode 100644
index 00000000..9b79cfbe
--- /dev/null
+++ b/algorithms/CPlusPlus/.gitignore
@@ -0,0 +1,2 @@
+.vscode/
+*.exe
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/Unique.cpp b/algorithms/CPlusPlus/Bit manupulation/Unique.cpp
new file mode 100644
index 00000000..0b4c6a56
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/Unique.cpp	
@@ -0,0 +1,20 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int unique(int a[],int n){
+    int num=0;
+    for(int i=0;i<n;i++){
+        num=a[i]^num;
+    }
+    return num;
+}
+
+int main(){
+    int n;
+    cin>>n;
+    int a[n];
+    for(int i=0;i<n;i++){
+        cin>>a[i];
+    }
+    cout<<unique(a,n);
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/Unique2.cpp b/algorithms/CPlusPlus/Bit manupulation/Unique2.cpp
new file mode 100644
index 00000000..fa34f581
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/Unique2.cpp	
@@ -0,0 +1,35 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int unique2(int a[],int n){
+    int num=0;
+    for(int i=0;i<n;i++)
+        num=num^a[i];
+    return num;    
+}
+int getbit(int n,int num){
+    return (n&(1<<num));
+}
+
+int main(){
+    int n;
+    cin>>n;
+    int a[n];
+    for(int i=0;i<n;i++){
+        cin>>a[i];
+    }
+    int num=unique2(a,n);
+    int c=0;
+    while(c<num){
+        if(num&(1<<c))
+        break;
+        c++;
+    }
+    int n1=0;
+    for(int i=0;i<n;i++){
+        if(getbit(a[i],c))
+         n1=n1^a[i];   
+    }
+    cout<<n1<<" "<<(n1^num);
+
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/Unique3.cpp b/algorithms/CPlusPlus/Bit manupulation/Unique3.cpp
new file mode 100644
index 00000000..a8b8f386
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/Unique3.cpp	
@@ -0,0 +1,22 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(){
+    int n;
+    cin>>n;
+    int a[n];
+    for(int i=0;i<n;i++)
+        cin>>a[i];
+
+    int sum=0,num=0;
+    for(int i=0;i<64;i++){
+        sum=0;
+        for(int j=0;j<n;j++){
+            if(a[j]&(1<<i))
+            sum++;
+        }
+        if(sum%3 !=0)
+        num=(num|(1<<i));
+    }
+    cout<<num;
+}
diff --git a/algorithms/CPlusPlus/Bit manupulation/bit_manupulation_methods.cpp b/algorithms/CPlusPlus/Bit manupulation/bit_manupulation_methods.cpp
new file mode 100644
index 00000000..ae68f8ce
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/bit_manupulation_methods.cpp	
@@ -0,0 +1,26 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int setbit(int n,int pos){
+    return (n|(1<<pos));
+}
+int getbit(int n,int pos){
+    return (( n &(1<<pos) )!=0);
+}
+int removebit(int n,int pos){
+    return (n &(~(1<<pos)));
+}
+int updatebit(int n,int pos,int val){
+    int a=n & (~(1<<pos));
+    return (a|(val<<pos));
+}
+
+int main(){
+    int n,p,v;
+    cin>>n>>p;
+    cout<<getbit(n,p)<<endl;
+    cout<<setbit(n,p)<<endl;
+    cout<<removebit(n,p)<<endl;
+    cin>>v;
+    cout<<updatebit(n,p,v)<<endl;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/number_of_ones.cpp b/algorithms/CPlusPlus/Bit manupulation/number_of_ones.cpp
new file mode 100644
index 00000000..6732a0f2
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/number_of_ones.cpp	
@@ -0,0 +1,17 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int countones(int n){
+    int count=0;
+    while(n>0){
+        n=(n&(n-1));          
+        count++;
+    }
+    return count;
+}
+
+int main(){
+    int n;
+    cin>>n;
+    cout<<countones(n);
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/power_of_two.cpp b/algorithms/CPlusPlus/Bit manupulation/power_of_two.cpp
new file mode 100644
index 00000000..e77d612a
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/power_of_two.cpp	
@@ -0,0 +1,13 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int check2power(int n){
+    
+    return ((n & (n-1))==0);
+}
+
+int main(){
+    int n;
+    cin>>n;
+    cout<<check2power(n);
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Bit manupulation/subsets.cpp b/algorithms/CPlusPlus/Bit manupulation/subsets.cpp
new file mode 100644
index 00000000..1d39b89b
--- /dev/null
+++ b/algorithms/CPlusPlus/Bit manupulation/subsets.cpp	
@@ -0,0 +1,18 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(){
+    int n;
+    cin>>n;
+    int a[n];
+    for(int i=0;i<n;i++)
+        cin>>a[i];
+
+    for(int i=0;i<(1<<n);i++){
+        for(int j=0;j<n;j++){
+            if(i&(1<<j))
+                cout<<a[j]<<" ";
+        }
+        cout<<endl;
+    }
+}
diff --git a/algorithms/CPlusPlus/Number system/binary_addition.cpp b/algorithms/CPlusPlus/Number system/binary_addition.cpp
new file mode 100644
index 00000000..c75918af
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/binary_addition.cpp	
@@ -0,0 +1,85 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int reverse(int n){
+    int ans=0,d;
+    while(n>0){
+        d=n%10;
+        ans=ans*10 + d;
+        n=n/10;
+    }
+    return ans;
+}
+
+int binary_addition(int a,int b){
+    int add=0,carry=0;
+    while(a>0 && b>0){
+
+        if(a%2==1 && b%2==1){
+            add=add*10 + carry;
+            carry=1;
+        }
+        else if((a%2==1 && b%2==0) || (a%2==0 && b%2==1)){
+            if(carry==1){
+                add=add*10 + 0;
+                carry=1;
+            }
+            else{
+                add=add*10 + 1;
+                carry=0;
+            }
+        }
+        else{
+            add = add*10 + carry;
+            carry=0;
+        }
+        a=a/10;
+        b=b/10;
+    }
+    while(a>0){
+        if(a%2==1){
+            if(carry==1){
+                carry=1;
+                add=add*10+0;
+            }
+            else{
+                carry=0;
+                add=add*10 + 1;
+            }
+        }
+        else{
+            add=add*10 +carry;
+            carry=0;
+        }
+        a=a/10;
+    }
+    while(b>0){
+        if(b%2==1){
+            if(carry==1){
+                carry=1;
+                add=add*10+0;
+            }
+            else{
+                carry=0;
+                add=add*10 + 1;
+            }
+        }
+        else{
+            add=add*10 +carry;
+            carry=0;
+        }
+        b=b/10;
+    }
+    if(carry==1){
+        add=add*10 +1;
+    }
+    add=reverse(add);
+    return add;
+}
+
+int main(){
+    int a,b;
+    cin>>a>>b;
+    int add=binary_addition(a,b);
+    cout<<add;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/binary_to_decimal.cpp b/algorithms/CPlusPlus/Number system/binary_to_decimal.cpp
new file mode 100644
index 00000000..612eaf73
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/binary_to_decimal.cpp	
@@ -0,0 +1,18 @@
+#include<bits/stdc++.h>
+using namespace std;
+int binarytodecimal(int n){
+    int two=1,r,num=0;
+    while(n>0){
+        r=n%10;
+        num=num + two*r;
+        two*=2;
+        n/=10;
+    }
+    return num;
+}
+int main(){
+    int n;
+    cin>>n;
+    int decimal=binarytodecimal(n);
+    cout<<decimal;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/decimal_to_binary.cpp b/algorithms/CPlusPlus/Number system/decimal_to_binary.cpp
new file mode 100644
index 00000000..85cc58a6
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/decimal_to_binary.cpp	
@@ -0,0 +1,24 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int decimaltobinary(int n){
+    int max=1;
+    while(max<=n){
+        max=max*2;
+    }
+    max/=2;             
+    int num=0;
+    while(max>=1){
+        num=num*10 + n/max;
+        n-=max*(n/max);
+        max=max/2;        
+    }
+    return num;
+}
+
+int main(){
+    int n;
+    cin>>n;
+    int binary=decimaltobinary(n);
+    cout<<binary;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/decimal_to_hexa.cpp b/algorithms/CPlusPlus/Number system/decimal_to_hexa.cpp
new file mode 100644
index 00000000..c63ada32
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/decimal_to_hexa.cpp	
@@ -0,0 +1,29 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+string decimal_to_hexa(int n){
+    int multipler=1;
+    while(multipler<=n)
+        multipler*=16;
+    multipler/=16;
+    string num="";
+    int d;
+    while(multipler>=1){
+        d=n/multipler;
+        if(d>9){
+            char c='A'+(d-10);
+            num= num + c;
+        }
+        else
+        num=num + to_string(d);
+        n=n-(d*multipler);
+        multipler/=16;
+    }
+    return num;
+}
+int main(){
+    int n;
+    cin>>n;
+    string hexa=decimal_to_hexa(n);
+    cout<<hexa;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/decimal_to_octal.cpp b/algorithms/CPlusPlus/Number system/decimal_to_octal.cpp
new file mode 100644
index 00000000..40afbcb6
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/decimal_to_octal.cpp	
@@ -0,0 +1,24 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int decimal_to_octal(int n){
+    int multiplier=1;
+    while(multiplier<=n){
+        multiplier*=8;
+    }
+    
+    multiplier/=8;
+    int num=0;
+    while(multiplier>=1){
+        num=num*10 + n/multiplier;
+        n=n - multiplier*(n/multiplier);
+        multiplier/=8;        
+    }
+    return num;
+}
+int main(){
+    int n;
+    cin>>n;
+    int octal=decimal_to_octal(n);
+    cout<<octal;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/hexa_to_decimal.cpp b/algorithms/CPlusPlus/Number system/hexa_to_decimal.cpp
new file mode 100644
index 00000000..b9d80b04
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/hexa_to_decimal.cpp	
@@ -0,0 +1,24 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int hexa_to_decimal(string n){
+    int l=n.size();
+    l=l-1;
+    int ans=0,x=1;
+    while(l>=0){
+        if(n[l]>='0' && n[l]<='9')
+            ans+=(n[l]-'0')*x;
+        else   
+            ans+=x*(n[l]-'A'+10);
+        x*=16;
+        l--;     
+    }
+    return ans;
+}
+
+int main(){
+    string s;
+    cin>>s;
+    int decimal=hexa_to_decimal(s);
+    cout<<decimal;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Number system/octal_to_decimal.cpp b/algorithms/CPlusPlus/Number system/octal_to_decimal.cpp
new file mode 100644
index 00000000..9ab2f46b
--- /dev/null
+++ b/algorithms/CPlusPlus/Number system/octal_to_decimal.cpp	
@@ -0,0 +1,20 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int octal_to_decimal(int n){
+    int num=0,r,multiplier=1;
+    while(n>0){
+        r=n%10;
+        num=num + (r*multiplier);
+        n=n/10;
+        multiplier=multiplier*8;  
+    }
+    return num;
+}
+
+int main(){
+    int n;
+    cin>>n;
+    int decimal=octal_to_decimal(n);
+    cout<<decimal;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Set/Multiset.cpp b/algorithms/CPlusPlus/Set/Multiset.cpp
new file mode 100644
index 00000000..1738d218
--- /dev/null
+++ b/algorithms/CPlusPlus/Set/Multiset.cpp
@@ -0,0 +1,24 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(){
+    multiset<int> ms;
+    ms.insert(1);
+    ms.insert(1);
+    ms.insert(1);
+    ms.insert(2);
+    ms.insert(3);
+    ms.insert(5);
+    for(auto el:ms)
+    cout<<el;
+    cout<<endl;
+    ms.erase(ms.find(1));
+    for(auto el:ms)
+    cout<<el;
+    cout<<endl;
+    ms.erase(5);
+    ms.erase(1);
+    for(auto el:ms)
+    cout<<el;
+    cout<<endl;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Set/Set.cpp b/algorithms/CPlusPlus/Set/Set.cpp
new file mode 100644
index 00000000..3b88ed55
--- /dev/null
+++ b/algorithms/CPlusPlus/Set/Set.cpp
@@ -0,0 +1,31 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(){
+    set<int> s;
+    s.insert(1);
+    s.insert(2);
+    s.insert(3);
+    s.insert(4);
+    s.insert(2);
+    for(auto el:s)
+    cout<<el;
+    cout<<endl;
+    for(auto el=s.begin();el!=s.end();el++)
+    cout<<*el;
+    cout<<endl;
+    for(auto el=s.rbegin();el!=s.rend();el++)
+    cout<<*el;
+    cout<<endl;
+
+
+    set<int,greater<int>> s1;
+    s1.insert(1);
+    s1.insert(2);
+    s1.insert(3);
+    s1.insert(4);
+    s1.insert(2);
+    for(auto el:s1)
+    cout<<el;
+    cout<<endl;
+}
\ No newline at end of file
diff --git a/algorithms/CPlusPlus/Set/unordered_set.cpp b/algorithms/CPlusPlus/Set/unordered_set.cpp
new file mode 100644
index 00000000..0f0bc1bf
--- /dev/null
+++ b/algorithms/CPlusPlus/Set/unordered_set.cpp
@@ -0,0 +1,13 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(){
+    unordered_set<int> us;
+    us.insert(2);
+    us.insert(1);
+    us.insert(4);
+    us.insert(5);
+    for(auto el:us)
+    cout<<el;
+    cout<<endl;
+}
\ No newline at end of file