C++ Programming Code Examples
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Program to print first 100 Ramanujan Numbers by two ways
/* Program to print first 100 Ramanujan Numbers by two ways */
/*
Description: Programme to Print first 100 Ramanujan Numbers
by TWO WAYS
1st way is printing Ramunajan Numbers from RN
taking RN from 0 to INFINITY and print first 100 numbers.
2nd way is to clacualte RN numbers from L M N P of formula
RN= L^3 + M^3 = N^3 + P^3 and sort the RN numbers and print first
100 Numbers
RN=RAMANUJAN NUMBERS
*/
#include<iostream.h> //Include Header Files
#include<math.h>
using namespace std;
template <class X>X cube(X a)//TEMPLATE to calculate CUBE of a number
and
{ //Return the CUBE
return (a*a*a);//Return CUBE
}
class Ramanujan{//CLASS to PRINT RN in two ways
public:
void fromRN();//PRINT RN from RN
void fromLMNP();//PRINT RN from LMNP values
};
void Ramanujan::fromLMNP()//Start of LMNP
{
int L=0,M=0,N=0,P=0;//integer L,M,N,P to calculate RN
int a[200];//ARRAY to store RN calculated from L,M,N,P
int temp;//Integer to SWAP for sorting.
int i=0,j=0;//Integer's for sorting ARRAY
int CAL;//Integer to store how many values calculated for RN
cout<<"
Calculating RN numbers from LMNP values Please
Wait.........
";
for(L=0;L<128;L++)//L
for(M=0;M<170;M++)//M
for(N=0;N<170;N++)//N
for(P=0;P<205;P++)//P
{if(L<M && M<N && N<P)//if the Condition Satisfy
{ //FINDING the PAIRS MATCHING RN numbers
if((cube(L)+cube(M))==(cube(N)+cube(P)))
{ a[i]=cube(L)+cube(M);i++;}
else if((cube(L)+cube(N))==(cube(M)+cube(P)))
{a[i]=cube(L)+cube(N);i++;}
else if((cube(L)+cube(P))==(cube(N)+cube(M)))
{a[i]=cube(N)+cube(M);i++;}
}//END of IF
}//END of FOR LOOP
CAL=i;//CAL stores how many values calculated for RN
i=0;
cout<<"
SORTING Please Wait.........
";
for (i=0; i<CAL-1; i++) //For LOOP TO SORT THE ARRAY
{
for (j=0; j<CAL-1-i; j++)
if (a[j+1] < a[j])
{ // compare the two values
temp = a[j]; //swap a[j] and a[j+1]
a[j] = a[j+1];
a[j+1] = temp;
}
}
i=0;//i=0
cout<<"
Ramanujan Numbers are..........";
//TO print 100 RN numbers
do
{
cout<<"
"<<(i+1)<<" : "<<a[i];
i++;
}while(i<100);//condition for i
}//END of the MEMEBER fromLNMP
void Ramanujan::fromRN()//Start of RN
{
double k,l,mk,care=0,kmk=0;
int ri=0;//RN Nunber
int h,mc,m,Lo;//h is HIGEST (ie L)
//mc is to calculate MINIMUM(i.e M)
//MINIMUM (i.e M)
int i,j,flag=1;//FLAG to track the NUMBER of RN NUMBERS
l=(1.00/3.00);//for CUBE ROOT
cout<<"SLno L M N P =RN
";
for(ri=0;flag<=100;ri++)//FOR loop taking RN from 0
{ care=0;//FLAG to track number of times M occured
kmk=0;//FLAG to track number of NP occurance
k=(pow(ri,l));
for(;k>0&&care==0;k--){//LOOP to find M value
h=(int)k;
mc=((int)(ri-cube(h)));
mk=(pow(mc,l));
m=(int)mk;
if(m<mk)
m=m+1;
else
m=(int)mk;
if(cube(m)+cube(h)==ri)
{
care++;//to break the LOOP to find M value
}//END of IF
}//END of for LOOP to find M value
if((double)(cube(h)+cube(m))==ri)//IF LM found then calculate OP
for(i=m;i<=h;i++)//to calculate RN
for(j=h;j>=m;j--)
if((cube(i)+cube(j))==cube(m)+cube(h))//if FINDED NP also
{//then check the condition
if(i!=j&&i!=h&&i!=m&&j!=h&&j!=m&&h!=m&&(double)(cube(h)+cube(m))==ri&&(dou
ble)(cube(i)+cube(j))==ri)
{if(kmk==0){//if LMNP if found then PRINT RN
//printf("
%d: %d %d %d %d = %d",flag,i,j,h,m,ri);
cout<<"
"<<flag<<" "<<h<<" "<<m<<" "<<i<<" "<<j<<"= "<<ri;
flag++;//to increment the RN found flag and
kmk++;//TO break the LOOP to find LM
}//END of IF
}//END of IF
//flag++;
} //END of FOR LOOP LM found
} //END of FOR LOOP taking RN from
} //END of RN
int main(){//MAIN PROOGRAMME
char choice;
Ramanujan rn;//object of Ramnujan class
do{
system("clear");//CLEAR SCREEN
//PRINT THE MENU
cout<<"##########Menu to Calculate Ramanujan
Numbers###############################
";
cout<<"1: Calculate RN number by checking RN number and print
first 100 Numbers
";
cout<<" (Takes more time........)
";
cout<<"2: Calculate RN fumber by claculating L, M, N,P and
print
first 100 Numbers
";
cout<<"3: Quit from Menu
";
cout<<"###################################################################
#########
";
cout<<"Enter Your choice :";
cin>>choice;//USER to select choice
if(choice=='1')//If choice 1 then print RN from RN number
{
rn.fromRN();//calling member to print RN from RN number
cout<<"
Do you want to Continue(y or Y) else Any key to exit
:";
cin>>choice;
}
else if(choice=='2')//If choice 2 then print RN from LNMP
{
rn.fromLMNP();//calling member to print print RN from LNMP
values
cout<<"
Do you want to Continue(y or Y) else Any key to exit
:";
cin>>choice;
}
else if(choice=='3')//to QUIT
{
cout<<"
Bye:..............
";
}
else//if worng choice entered
{
cout<<"
You Entered Wrong Choice Please select correct
";
cout<<"
Do you want to Continue(y or Y) else Any key to exit
:";
cin>>choice;
}
}while(choice=='y'||choice=='Y');//condition for choice
return 0; //return 0
} //End of main Programme
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