diff --git a/Abundant_number_q23.cpp b/Abundant_number_q23.cpp
new file mode 100644
index 0000000..f2255fd
--- /dev/null
+++ b/Abundant_number_q23.cpp
@@ -0,0 +1,22 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int sum = 0 ;
+  for(int i = 1;i<n ;i++)
+  {
+    if(n%i==0)
+    {
+      sum+=i;
+    }
+  }
+  if(sum>n)
+  {
+    cout<<"Its a Abundant number";
+  }else{
+    cout<<"its not a Abundant number";
+  }
+}
\ No newline at end of file
diff --git a/Automorphic_number_q21.cpp b/Automorphic_number_q21.cpp
new file mode 100644
index 0000000..848658f
--- /dev/null
+++ b/Automorphic_number_q21.cpp
@@ -0,0 +1,23 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int s = n*n;
+  int temp = n;
+  int c = 0;
+  while(temp !=0)
+  {
+    temp /= 10;
+    c++;
+  }
+  int k = s % (int)pow(10,c);
+  if(k == n)
+  {
+    cout<<"its a Automorphic number";
+  }else{
+    cout<<"its not a Automorphic number";
+  }
+}
\ No newline at end of file
diff --git a/Factorial_of_a_Number_q15.cpp b/Factorial_of_a_Number_q15.cpp
new file mode 100644
index 0000000..1ca762e
--- /dev/null
+++ b/Factorial_of_a_Number_q15.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+using namespace std;
+int fact(int n)
+{
+  if(n<=1)
+  return 1;
+  return n * fact(n-1);
+}
+int main()
+{
+    int n;
+    cin >> n;
+    cout<<fact(n);
+    
+}
\ No newline at end of file
diff --git a/Harshad_number_q22.cpp b/Harshad_number_q22.cpp
new file mode 100644
index 0000000..2159d24
--- /dev/null
+++ b/Harshad_number_q22.cpp
@@ -0,0 +1,21 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int c = 0;
+  while(temp !=0)
+  {
+    c +=temp%10;
+    temp /= 10;
+  }
+  if(n%c ==0)
+  {
+    cout<<"its a Harshad number";
+  }else{
+    cout<<"its not a Harshad number";
+  }
+}
\ No newline at end of file
diff --git a/ManjariNK_even_or_odd_q4.cpp b/ManjariNK_even_or_odd_q4.cpp
new file mode 100644
index 0000000..b40df3c
--- /dev/null
+++ b/ManjariNK_even_or_odd_q4.cpp
@@ -0,0 +1,9 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int num;
+    cin>>num;
+    num%2==0 ? cout<<"Even":cout<<"Odd";
+    return 0;
+}
diff --git a/ManjariNK_positiveornegative_q2.cpp b/ManjariNK_positiveornegative_q2.cpp
new file mode 100644
index 0000000..4a8414b
--- /dev/null
+++ b/ManjariNK_positiveornegative_q2.cpp
@@ -0,0 +1,17 @@
+#include<iostream>
+using namespace std;
+int main(){
+    int number;
+    cin>>number;
+    if(number>0)
+    {
+        cout<<"The number is Positive";
+    }
+    else if(number<0)
+    {
+        cout<<"The number is Negative";
+    }
+    else{
+        cout<<"The number is Zero";
+    }
+}
diff --git a/ManjariNK_sum_of_naturalNumbers_inRange_q5.cpp b/ManjariNK_sum_of_naturalNumbers_inRange_q5.cpp
new file mode 100644
index 0000000..e6f9641
--- /dev/null
+++ b/ManjariNK_sum_of_naturalNumbers_inRange_q5.cpp
@@ -0,0 +1,14 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int num1;
+    int num2;
+    cin>>num1>>num2;
+    int sum=0;
+    for(int i=num1;i<num2;i++)
+    {
+        sum+=i;
+    }
+    cout<<sum;
+}
diff --git a/ManjariNK_sumofdigits_q7.cpp b/ManjariNK_sumofdigits_q7.cpp
new file mode 100644
index 0000000..5854e50
--- /dev/null
+++ b/ManjariNK_sumofdigits_q7.cpp
@@ -0,0 +1,16 @@
+#include <iostream>
+using namespace std;
+
+int main() 
+{
+    int num;
+    cin>>num;
+   int temp=num,sum=0;
+   while(temp!=0)
+   {
+     sum+=temp%10;
+     temp/=10;
+   }
+   cout<<sum;
+return 0;
+}
diff --git a/ManjariNK_sumofnaturalnumbers_q1.cpp b/ManjariNK_sumofnaturalnumbers_q1.cpp
new file mode 100644
index 0000000..58b584e
--- /dev/null
+++ b/ManjariNK_sumofnaturalnumbers_q1.cpp
@@ -0,0 +1,14 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int num;
+    int sum=0;
+    cin>>num;
+    for(int i=1;i<=num;i++)
+    {
+        sum+=i;
+    }
+    cout<<sum;
+
+}
diff --git a/Manjari_leapyear_q6.cpp b/Manjari_leapyear_q6.cpp
new file mode 100644
index 0000000..d911032
--- /dev/null
+++ b/Manjari_leapyear_q6.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int year;
+    cin>>year;
+    if((year%4==0 && year%100!=0) || (year%400==0))
+    {
+        cout<<year<<" is leap year";
+    }
+    else{
+        cout<<year<<" is not leap year";
+    }
+    return 0;
+}
diff --git a/Nth_Term_of_the_Fibonacci_Series_q14.cpp b/Nth_Term_of_the_Fibonacci_Series_q14.cpp
new file mode 100644
index 0000000..09c743c
--- /dev/null
+++ b/Nth_Term_of_the_Fibonacci_Series_q14.cpp
@@ -0,0 +1,18 @@
+#include<iostream>
+using namespace std;
+
+int main()
+{
+    int n;
+    cin >> n;
+
+    int a = 0, b = 1;
+
+    for(int i = 1; i < n; i++)
+    {
+        int next = a + b;
+        a = b;
+        b = next;
+    }
+    cout << a << " ";
+}
\ No newline at end of file
diff --git a/add_2fractions_q37.cpp b/add_2fractions_q37.cpp
new file mode 100644
index 0000000..0a07b63
--- /dev/null
+++ b/add_2fractions_q37.cpp
@@ -0,0 +1,21 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int gcd(int a , int b)
+{
+  if(b==0)
+  return a;
+  return gcd(b , a%b);
+}
+int main()
+{
+ int a , b, c, d;
+ cin>>a>>b>>c>>d;
+ int lcm = b*d/gcd(b,d);
+ int x ;
+   x = a*(lcm/b) + c*(lcm/d);
+   int g =gcd(x , lcm);
+  x=x/g;
+  lcm=lcm/g;
+ cout<<x<<"/"<<lcm;
+}
\ No newline at end of file
diff --git a/armstrong_in_give_range_q11.cpp b/armstrong_in_give_range_q11.cpp
new file mode 100644
index 0000000..27d5f0c
--- /dev/null
+++ b/armstrong_in_give_range_q11.cpp
@@ -0,0 +1,44 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+bool armstrong(int n)
+{
+  int temp = n;
+  int c=0;
+  if (n < 0) {
+        return false;
+    }
+  while(temp!=0)
+  {
+    temp /= 10;
+    c++;
+  }
+  if (n == 0) c = 1;
+  temp=n;
+  int a=0;
+  while(temp!=0)
+  {
+    int k = temp%10;
+    a=a+(int)pow(k,c);
+    temp /=10;
+  }
+  if(a==n){
+    return true;
+  }else{
+    return false;
+  }
+}
+int main()
+{
+  int n , m;
+  cin>>n>>m;
+  for(int i=n;i<m ;i++)
+  {
+    if(armstrong(i))
+    {
+      cout<<i<<" ";
+    }
+  }
+  
+  
+}
diff --git a/armstrong_q12.cpp b/armstrong_q12.cpp
new file mode 100644
index 0000000..46a3b28
--- /dev/null
+++ b/armstrong_q12.cpp
@@ -0,0 +1,33 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int c =0;
+  if (n < 0) {
+        cout << "Its not an armstrong number";
+        return 0;
+    }
+  while(temp!=0)
+  {
+    temp /= 10;
+    c++;
+  }
+  if (n == 0) c = 1;
+  temp=n;
+  int a=0;
+  while(temp!=0)
+  {
+    int k = temp%10;
+    a=a+pow(k,c);
+    temp /=10;
+  }
+  if(a==n){
+    cout<<"Its a armstrong number";
+  }else{
+    cout<<"its not an armstrong number";
+  }
+}
diff --git a/binary_to_decimal_q28.cpp b/binary_to_decimal_q28.cpp
new file mode 100644
index 0000000..69b1377
--- /dev/null
+++ b/binary_to_decimal_q28.cpp
@@ -0,0 +1,17 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int sum =0;
+  int c=0;
+  while(temp !=0)
+  {
+    sum += (temp%10) * pow(2,c++);
+    temp /=10;
+  }
+  cout<<sum;
+}
\ No newline at end of file
diff --git a/coordinate_lies_q34.cpp b/coordinate_lies_q34.cpp
new file mode 100644
index 0000000..1d11d5f
--- /dev/null
+++ b/coordinate_lies_q34.cpp
@@ -0,0 +1,23 @@
+#include<iostream>
+using namespace std;
+
+int main()
+{
+    int x, y;
+    cin >> x >> y;
+
+    if(x > 0 && y > 0)
+        cout << "1st Quadrant";
+    else if(x < 0 && y > 0)
+        cout << "2nd Quadrant";
+    else if(x < 0 && y < 0)
+        cout << "3rd Quadrant";
+    else if(x > 0 && y < 0)
+        cout << "4th Quadrant";
+    else if(x == 0 && y == 0)
+        cout << "Origin";
+    else if(x == 0)
+        cout << "Y-axis";
+    else
+        cout << "X-axis";
+}
\ No newline at end of file
diff --git a/decimal_to_binary_q31.cpp b/decimal_to_binary_q31.cpp
new file mode 100644
index 0000000..c208657
--- /dev/null
+++ b/decimal_to_binary_q31.cpp
@@ -0,0 +1,17 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+ int n;
+ cin>>n;
+ int temp =n;
+ int bi =0;
+ int c=0;
+ while(temp!=0)
+ {
+   bi=bi+(temp%2)*pow(10,c++);
+   temp/=2;
+ }
+ cout<<bi;
+}
\ No newline at end of file
diff --git a/decimal_to_hexadecimal_q33.cpp b/decimal_to_hexadecimal_q33.cpp
new file mode 100644
index 0000000..e6fb25f
--- /dev/null
+++ b/decimal_to_hexadecimal_q33.cpp
@@ -0,0 +1,22 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+ int n;
+ cin>>n;
+ int temp =n;
+ string bi="";
+ while(temp!=0)
+ {
+   int k = (temp%16);
+   if(k>=10)
+   {
+     bi= (char)(k+55)+bi;
+   }else{
+   bi=char(k +'0')+bi;
+   }
+   temp/=16;
+ }
+ cout<<bi;
+}
\ No newline at end of file
diff --git a/decimal_to_octacl_q32.cpp b/decimal_to_octacl_q32.cpp
new file mode 100644
index 0000000..d2f1413
--- /dev/null
+++ b/decimal_to_octacl_q32.cpp
@@ -0,0 +1,17 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+ int n;
+ cin>>n;
+ int temp =n;
+ int bi =0;
+ int c=0;
+ while(temp!=0)
+ {
+   bi=bi+(temp%8)*pow(10,c++);
+   temp/=8;
+ }
+ cout<<bi;
+}
\ No newline at end of file
diff --git a/factor_q16.cpp b/factor_q16.cpp
new file mode 100644
index 0000000..b741a95
--- /dev/null
+++ b/factor_q16.cpp
@@ -0,0 +1,14 @@
+#include<iostream>
+using namespace std;
+int main(){
+  int n;
+  cin>>n;
+  for(int i=1;i<=n/2;i++)
+  {
+    if(n%i==0)
+    {
+      cout<<i<<" ";
+    }
+  }
+  cout<<n;
+}
\ No newline at end of file
diff --git a/fibonacci_q13.cpp b/fibonacci_q13.cpp
new file mode 100644
index 0000000..fdb23ac
--- /dev/null
+++ b/fibonacci_q13.cpp
@@ -0,0 +1,18 @@
+#include<iostream>
+using namespace std;
+
+int main()
+{
+    int n;
+    cin >> n;
+
+    int a = 0, b = 1;
+
+    for(int i = 1; i <= n; i++)
+    {
+        cout << a << " ";
+        int next = a + b;
+        a = b;
+        b = next;
+    }
+}
\ No newline at end of file
diff --git a/friendly_pairs_q24.cpp b/friendly_pairs_q24.cpp
new file mode 100644
index 0000000..9a311c9
--- /dev/null
+++ b/friendly_pairs_q24.cpp
@@ -0,0 +1,29 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n,m;
+  cin>>n>>m;
+  int sum = 0 , s=0 ;
+  for(int i = 1;i<n ;i++)
+  {
+    if(n%i==0)
+    {
+      sum+=i;
+    }
+  }
+    for(int i = 1;i<m ;i++)
+  {
+    if(m%i==0)
+    {
+      s+=i;
+    }
+  }
+  if(sum*m == s*n)
+  {
+    cout<<"Its a friendly pair";
+  }else{
+    cout<<"its not a friendly pair";
+  }
+}
\ No newline at end of file
diff --git a/gcd_q27.cpp b/gcd_q27.cpp
new file mode 100644
index 0000000..794d93a
--- /dev/null
+++ b/gcd_q27.cpp
@@ -0,0 +1,13 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int gcd(int n  , int m)
+{
+  return m == 0 ? n : gcd(m , n%m);
+}
+int main()
+{
+  int n,m;
+  cin>>n>>m;
+ cout<<gcd(n ,m);
+}
\ No newline at end of file
diff --git a/handshake_exactly_once_q36.cpp b/handshake_exactly_once_q36.cpp
new file mode 100644
index 0000000..5db1465
--- /dev/null
+++ b/handshake_exactly_once_q36.cpp
@@ -0,0 +1,9 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+ int x;
+ cin>>x;
+ cout<<(x*(x-1))/2;
+}
\ No newline at end of file
diff --git a/hcf_q25.cpp b/hcf_q25.cpp
new file mode 100644
index 0000000..488c40b
--- /dev/null
+++ b/hcf_q25.cpp
@@ -0,0 +1,18 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n,m;
+  cin>>n>>m;
+  int hcf = 1;
+  for(int i = 1; i <= n || i <= m; i++)
+    {
+        if(n % i == 0 && m % i == 0)
+            hcf = i;
+    }
+
+    cout<<"HCF of "<<n<<" and "<<m<<" is "<<hcf;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/hexadecimal_to_decimal_q30.cpp b/hexadecimal_to_decimal_q30.cpp
new file mode 100644
index 0000000..770dfbb
--- /dev/null
+++ b/hexadecimal_to_decimal_q30.cpp
@@ -0,0 +1,26 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  string n;
+  cin>>n;
+  int base = 16;
+  int dec=0;
+  for(int i=n.length()-1 ;i>=0 ;i--)
+  {
+    if(n[i]>='0' && n[i]<='9')
+    {
+      dec+=(n[i] - '0')*base;
+    }else if(n[i]>='A' && n[i]<='F')
+    {
+      dec+=(n[i] - 'A')*base;
+    }else if(n[i]>='a' && n[i]<='f')
+    {
+      dec+=(n[i] - 'a')*base;
+    }
+    base*=16;
+  }
+  cout<<dec;
+  
+}
\ No newline at end of file
diff --git a/lcm_q26.cpp b/lcm_q26.cpp
new file mode 100644
index 0000000..fbba972
--- /dev/null
+++ b/lcm_q26.cpp
@@ -0,0 +1,29 @@
+#include<iostream>
+using namespace std;
+
+int gcd(int a, int b)
+{
+    while(b != 0)
+    {
+        int r = a % b;
+        a = b;
+        b = r;
+    }
+    return a;
+}
+
+int main()
+{
+    int a, b;
+    cin >> a >> b;
+
+    if(a == 0 || b == 0)
+    {
+        cout << "LCM = 0";
+        return 0;
+    }
+
+    int lcm = (a * b) / gcd(a, b);
+
+    cout << "LCM = " << lcm;
+}
\ No newline at end of file
diff --git a/manjariNK_Greatest_of_two_numbers_q3.cpp b/manjariNK_Greatest_of_two_numbers_q3.cpp
new file mode 100644
index 0000000..8bdd2cb
--- /dev/null
+++ b/manjariNK_Greatest_of_two_numbers_q3.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int num1;
+    int num2;
+    cin>>num1>>num2;
+    if(num1==num2)
+    {
+        cout<<"Both are equal";
+    }else{
+    num1>num2 ? cout<<num1<<" is greater than "<<num2 : cout<<num2<<" is greater than "<<num1;
+    }
+    return 0;
+}
diff --git a/number_of_digits_q40.cpp b/number_of_digits_q40.cpp
new file mode 100644
index 0000000..cf5b5cc
--- /dev/null
+++ b/number_of_digits_q40.cpp
@@ -0,0 +1,19 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int x;
+  cin>>x;
+  int temp=x;
+  int c=0;
+  while(temp!=0)
+  {
+    temp/=10;
+    c++;
+  }
+  if(x==0)
+  cout<<"number of digits = "<<1;
+  else
+  cout<<"number of digits = "<<c;
+}
\ No newline at end of file
diff --git a/number_sumof2primenumber_q41.cpp b/number_sumof2primenumber_q41.cpp
new file mode 100644
index 0000000..e6f4eaa
--- /dev/null
+++ b/number_sumof2primenumber_q41.cpp
@@ -0,0 +1,33 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+bool isprime(int n)
+{
+  if(n<=1)
+  return false;
+  for(int i=2;i*i<=n;i++)
+  {
+    if(n%i==0)
+    return false;
+  }
+  return true;
+}
+int main()
+{
+  int x;
+  cin>>x;
+
+  for(int i=2;i<=x/2;i++)
+  {
+    if(isprime(i) && isprime(x-i))
+    {
+      if(x==i+(x-i))
+      {
+        cout<<" can be represented as sum of two prime numbers";
+        return 0;
+      }
+    }
+
+  }
+  cout<<"cant be represented ";
+}
\ No newline at end of file
diff --git a/occurance_q39.cpp b/occurance_q39.cpp
new file mode 100644
index 0000000..1338634
--- /dev/null
+++ b/occurance_q39.cpp
@@ -0,0 +1,25 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int x,y;
+  cin>>x>>y;
+  int temp=x;
+  int c=0;
+  if(y < 0 || y > 9)
+    {
+        cout << "Invalid digit";
+        return 0;
+    }
+    if(x == 0 && y == 0)
+        count = 1;
+ while(temp!=0)
+ {
+   int k = temp%10;
+   temp/=10;
+   if(k==y) 
+      c++;
+ }
+ cout<<y<<" occurs "<<c<<" times";
+}
\ No newline at end of file
diff --git a/octal_to_decimal_q29.cpp b/octal_to_decimal_q29.cpp
new file mode 100644
index 0000000..2ef0b42
--- /dev/null
+++ b/octal_to_decimal_q29.cpp
@@ -0,0 +1,17 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int sum =0;
+  int c=0;
+  while(temp !=0)
+  {
+    sum += (temp%10) * (int)pow(8,c++);
+    temp /=10;
+  }
+  cout<<sum;
+}
\ No newline at end of file
diff --git a/palindrome_or_not_q10.cpp b/palindrome_or_not_q10.cpp
new file mode 100644
index 0000000..295d254
--- /dev/null
+++ b/palindrome_or_not_q10.cpp
@@ -0,0 +1,20 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int rev =0;
+  while(temp!=0)
+  {
+    rev = rev*10 + temp%10;
+    temp=temp/10;
+  }
+  if(n==rev)
+  {
+    cout<<"Its a palindrome";
+  }else{
+    cout<<"Its not a palindrome";
+  }
+}
diff --git a/perfect_number_q19.cpp b/perfect_number_q19.cpp
new file mode 100644
index 0000000..47373c0
--- /dev/null
+++ b/perfect_number_q19.cpp
@@ -0,0 +1,21 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int sum=0;
+  for(int i=1;i<=n/2;i++)
+  {
+    if(n%i==0)
+    {
+      sum+=i;
+    }
+  }
+  if(sum==n)
+  {
+    cout<<"its a perfect number";
+  }else{
+    cout<<"Its not a perfect number";
+  }
+}
\ No newline at end of file
diff --git a/perfect_square_q20.cpp b/perfect_square_q20.cpp
new file mode 100644
index 0000000..0d6d38d
--- /dev/null
+++ b/perfect_square_q20.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int n;
+  cin>>n;
+  int r = sqrt(n) ;
+  if(r * r ==n )
+  {
+    cout<<"its a perfect square";
+  }else{
+    cout<<"its not a perfect square";
+  }
+}
\ No newline at end of file
diff --git a/permutation_q35.cpp b/permutation_q35.cpp
new file mode 100644
index 0000000..1fef152
--- /dev/null
+++ b/permutation_q35.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int fact(int n)
+{
+  if(n<=1)
+  return 1;
+  return n *fact(n-1);
+}
+int main()
+{
+ int x , y;
+ cin>>x>>y;
+ cout<<fact(x)/fact(x-y);
+}
\ No newline at end of file
diff --git a/power_of_number_q8.cpp b/power_of_number_q8.cpp
new file mode 100644
index 0000000..851c676
--- /dev/null
+++ b/power_of_number_q8.cpp
@@ -0,0 +1,15 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int base, expo;
+    cin>>base>>expo;
+    int res=1;
+    for(int i=1;i<=expo;i++)
+    {
+        res*=base;
+    }
+    cout<<res;
+    return 0;
+    
+}
diff --git a/prime_factor_q17.cpp b/prime_factor_q17.cpp
new file mode 100644
index 0000000..775cb7e
--- /dev/null
+++ b/prime_factor_q17.cpp
@@ -0,0 +1,26 @@
+#include<iostream>
+using namespace std;
+bool prime(int n)
+{
+  if (n <= 1) return false;
+
+    for (int i = 2; i * i <= n; i++) {
+        if (n % i == 0)
+            return false;
+    }
+    return true;
+}
+int main(){
+  int n;
+  cin>>n;
+  for(int i=1;i<=n;i++)
+  {
+    if(n%i==0)
+    {
+      if(prime(i))
+      {
+      cout<<i<<" ";
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/prime_number_with_in range_q9.cpp b/prime_number_with_in range_q9.cpp
new file mode 100644
index 0000000..73c0994
--- /dev/null
+++ b/prime_number_with_in range_q9.cpp	
@@ -0,0 +1,27 @@
+#include <iostream>
+#include <cmath>
+using namespace std;
+
+bool isPrime(int n) {
+    if (n <= 1) return false;
+
+    for (int i = 2; i <= sqrt(n); i++) {
+        if (n % i == 0) {
+            return false;
+        }
+    }
+    return true;
+}
+
+int main() {
+    int range;
+    cin >> range;
+    
+    for(int i =0 ;i<range ; i++)
+    {
+    if (isPrime(i))
+        cout << i<<" ";
+    }
+
+    return 0;
+}
diff --git a/replace0_with1_q38.cpp b/replace0_with1_q38.cpp
new file mode 100644
index 0000000..356e449
--- /dev/null
+++ b/replace0_with1_q38.cpp
@@ -0,0 +1,21 @@
+#include<iostream>
+#include<cmath>
+using namespace std;
+int main()
+{
+  int x;
+  cin>>x;
+  int z=0,c=0;
+  while(x!=0)
+  {
+    int k = x%10;
+    if(k)
+    {
+      z=k*(int)pow(10,c++)+z;
+    }else{
+      z=1*(int)pow(10,c++)+z;
+    }
+    x/=10;
+  }
+  cout<<z;
+}
\ No newline at end of file
diff --git a/strong_number_q18.cpp b/strong_number_q18.cpp
new file mode 100644
index 0000000..5b0df02
--- /dev/null
+++ b/strong_number_q18.cpp
@@ -0,0 +1,27 @@
+#include<iostream>
+using namespace std;
+int fact(int k)
+{
+  if(k<=1)
+  return 1;
+  return k * fact(k-1);
+}
+int main()
+{
+  int n;
+  cin>>n;
+  int temp = n;
+  int sum=0;
+  while(temp != 0)
+  {
+    int k = temp%10;
+    sum +=fact(k);
+    temp /=10;
+  }
+  if(sum==n)
+  {
+    cout<<"Its a strong number";
+  }else{
+    cout<<"Its not a strong number";
+  }
+}
\ No newline at end of file