Computer Programming Lab 10

Lab 10: Function Overloading and Recursion

Exercise 1                                                                                                                                             

Write a C++ program for calculating grades of students.

            int main():

·         prompt user for the number of subjects for which he/she wants to calcuclate the grade 2 or 3.

·         prompt for marks with respect to their early selection

·         call calgrades() according to their selection.

o   For example calgrades(s1,s2) // for two subjects.

o   calgrades(s1,s2,s3) // for three subjects.

            Calgrades():

·         Function(s) must be overloaded accordingly.

·         These functions determine the grade of student on following criteria:

A grade : 87 - 100

B grade : 75 – 86

C grade : 65 – 74

D grade : 50 – 64

F grade : < 50

Source Code:

#include<iostream>

using namespace std;

char calgrades(int,int);

char calgrades(int,int,int);

int main()

{

int n;

cout<<"enter number of subjects:";

cin>>n;

if(n==3){

int a,b,c;

cout<<"enter marks respectively:";

cin>>a>>b>>c;

char r=calgrades(a,b,c);

cout<<"GRADE:"<<r;

}

if(n==2)

{

int a,b;

cout<<"enter marks respectively:";

cin>>a>>b;

char r=calgrades(a,b);

cout<<"GRADE:"<<r;

}

}

char calgrades(int x ,int y)

{

int temp=x+y;

int sum=temp/2;

if(sum>=50&&sum<=64)

return 'D';

if(sum>=65&&sum<=74)

return 'C';

if(sum>=75&&sum<=86)

return 'B';

if(sum>=87&&sum<=100)

return 'A';

else

return 'F';

}

char calgrades(int x,int y,int z)

{

int sum,temp;

temp=x+y+z;

sum=temp/3;

if(sum>=50&&sum<=64)

return 'D';

if(sum>=65&&sum<=74)

return 'C';

if(sum>=75&&sum<=86)

return 'B';

if(sum>=87&&sum<=100)

return 'A';

else

return 'F';

}

Exercise 2                                                                                                                                             

Write a C++ that contains following functions:

int main():

·         prompt user to enter numbers for comparison.

·         Minimum numbers user can enter are 2 and maximum upto 4.

·         call comparison() method with two, three and four parameters.

int comparison():

·         this function determine the smallest and largest number

·         print the smallest and largest number

·         this function(s) must be overloaded

Source Code: 

#include<iostream>

using namespace std;

void comp(int,int);

void comp(int,int,int);

void comp(int,int,int,int);

int main()

{

int n,a,b,c,d;

cout<<"enter choice :";

cin>>n;

if(n==2)

{

cout<<"enter 2 numbers respectively:"<<endl;

cin>>a>>b;

comp(a,b);

}

if(n==3){

cout<<"enter 3 numbers respectively:"<<endl;

cin>>a>>b>>c;

comp(a,b,c);

}

if(n==4)

{

cout<<"enter 4 numbers respectively:"<<endl;

cin>>a>>b>>c>>d;

comp(a,b,c,d);

}

}

void comp(int x,int y)

{

if(x>y)

cout<<x<<" is greater and "<<y<<" is smaller";

else

cout<<y<<" is greater and "<<x<<" is smaller";

}

void comp(int x,int y,int z){

if(x>y&&y>z)

cout<<x<<" is greater and "<<z<<" is smaller";

if(y>z&&z>x)

cout<<y<<" is greater and "<<x<<" is smaller";

if(z>x&&x>y)

cout<<z<<" is greater and "<<y<<" is smaller";

}

void comp(int x,int y,int z,int w){

if(x>y&&y>z&&z>w)

cout<<x<<" is greater and "<<w<<" is smaller";

if(y>z&&z>w&&w>x)

cout<<y<<" is greater and "<<x<<" is smaller";

if(z>w&&w>x&&x>y)

cout<<z<<" is greater and "<<y<<" is smaller";

if(w>x&&x>y&&y>z)

{

cout<<w<<" is greater and "<<z<<" is smaller";

}

}

RECURSION

Exercise 3                                                                                                                                             

Write a recursive function that prints the numbers between 1 to n in a reverse order.

Source Code:

#include <iostream>

using namespace std;

int recur(int x)

{

cout<<x<<" ";

if(x<=1)

return 1;

else

return recur(x-1);

}

int main()

{

int n;

cout<<"enter number to generate series in reverse order:";

cin>>n;

recur(n);

return 0;

}

Exercise 3                                                                                                                                             

Write a recursive function that prints the numbers between 1 to n in a reverse order.Exercise 4     

Write a C++ program that perform following task:

int main():

·         ask user to enter a positive number, store it in variable N.

·         You have to calculate 1+2+3+4+……+N with fuction int sum().

·         Print the result.

            int sum():

·         this function calculate the sum of series from 1 to N.

·         this fuction must be recursion function.

Source Code:

#include<iostream>

using namespace std;

int sum(int x)

{

  if(x==1)

return 1;

else

return x+sum(x-1);

}

int main()

{

int n,temp,sum1=0;

cout<<"enter number: 1 to ";

cin>>n;

temp=n;

int result=sum(temp);

cout<<"SUM="<<result;

}

Exercise 5                                                                                                                                             

Write a C++ program that perform following task:

int main():

·         Ask user to enter a positive number, store it in variable N.

·         You have to calculate  Fibonacci number with fuction int fab().

·         Print the result.

            int fab():

·         this function calculate the Fibonacci number.

o   0, 1, 1, 2, 3, 5, 8, 13, 21, 34,..

o   fab(0) = 0, fab(1) = 1

o   fab(n) = fab(n-1) + fab(n-2)  where n>1

Source Code:

#include<iostream>

using namespace std;

int fib(int x)

{

if(x==1||x==0)

{

return x;

}

else

return fib(x-1)+fib(x-2);

}

int main()

{

int n;

cout<<"enter n:";

cin>>n;

for(int i=0;i<=n;i++)

{

cout<<" "<<fib(i);

}

}