Program of magic. magic.cpp

#include<iostream.h>
#include<conio.h>
int main()
{
   
    int i,ans=0;
    clrscr();
    cout<<"\n Choose one number in your mind from 1 to 63 \n";
    cout<<"\n 1    3    5    7    9    11    13    15 \n";
    cout<<"\n 17    19    21    23    25    27    29    31 \n";
    cout<<"\n 33    35    37    39    41    43    45    47 \n";
    cout<<"\n 49    51    53    55    57    59    61    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+1;
    }
    else
    {
        ans=ans;
    }


    cout<<"\n 2    3    6    7    10    11    14    15 \n";
    cout<<"\n 18    19    22    23    26    27    30    31 \n";
    cout<<"\n 34    35    38    39    42    43    46    47 \n";
    cout<<"\n 50    51    54    55    58    60    62    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+2;
    }
    else
    {ans=ans;}

    cout<<"\n 4    5    6    7    12    13    14    15 \n";
    cout<<"\n 20    21    22    23    28    29    30    31 \n";
    cout<<"\n 36    37    38    39    44    45    46    47 \n";
    cout<<"\n 52    53    54    55    60    61    62    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+4;
    }else
    {ans=ans;}
    cout<<"\n 8    9    10    11    12    13    14    15 \n";
    cout<<"\n 24    25    26    27    28    29    30    31 \n";
    cout<<"\n 40    41    42    43    44    45    46    47 \n";
    cout<<"\n 56    57    58    59    60    61    62    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+8;
    }else
    {ans=ans;}
    cout<<"\n 16    17    18    19    20    21    22    23 \n";
    cout<<"\n 24    25    26    27    28    29    30    31 \n";
    cout<<"\n 48    49    50    51    52    53    54    55 \n";
    cout<<"\n 56    57    58    59    60    61    62    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+16;
    }else
    {ans=ans;}

    cout<<"\n 32    33    34    35    36    37    38    39 \n";
    cout<<"\n 40    41    42    43    44    45    46    47 \n";
    cout<<"\n 48    49    50    51    52    53    54    55 \n";
    cout<<"\n 56    57    58    59    60    61    62    63 \n";
    cout<<"Write 0 if number in your mind is present or else write 1 if not present\n";
    cin>>i;
    if(i==0)
    {
        ans=ans+32;
    }else
    {ans=ans;}
    cout<<"The answer in your mind is : ";
    cout<<ans;
    getch();
    return 0;
}

Program to find GCD of two numbers

#include<iostream.h>
int main()
{
int first_number,second_number,gcd,i;
cout<<"Enter First Number : ";
cin>>first_number;

cout<<"Enter Second Number: ";
cin>>second_number;

for(i=1;i<=first_number&&i<=second_number;i++)
{

     if(first_number%i==0 && second_number%i == 0 )
{
                     gcd=i;

    }

}

cout<<"Greatest Common Division (GCD):"<<gcd<<endl;
return 0;
}

******Output******

Enter First Number: 9

Enter Second Number: 24

Greatest Common Division (GCD):3 

What is GCD of two numbers?
 It means a greatest number which divides both numbers
For example: Two numbers are 9 and 24
Numbers which divides both are 1 and 3 in which greatest number is 3
So 3 is the GCD of 9 and 24

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