Recursion Chapter 17 > Q.11

Q.11

#include <iostream>
using namespace std;

int func(int x);

void main()
{
cout << func(0) << endl;
cout << func(1) << endl;
cout << func(2) << endl;
cout << func(5) << endl;
}

int func(int x)
{
if (x==0)
return 2;
else if (x==1)
return 3;
else
return (func(x-1) + func(x-2));
}

Output:

Recursion: Chapter 17 > Q.10

Q.10:
#include <iostream>
using namespace std;

int test(int x, int y);

int main()
{
cout << test (5,10) << endl;
cout << test (3,9)  << endl;
}

int test(int x, int y)
{
if (x==y)
return x;
else if (x>y)
return (x+y);
else
return test(x+1,y-1);
}

Output:

Recursion Chapter 17 > Q.9

Q.9
#include <iostream>
using namespace std;

void exercise(int x);

int main()
{
while (1)
{
int x;
cout << "x: ";
cin >> x;

exercise(x);
cout << endl << endl;
}
}

void exercise(int x)
{
if (x>0 && x<10)
{
cout << x << " ";
exercise(x+1);
}
}

Output:

Recursion Chapter 17 > Q.8

Q. 8 (c):
#include <iostream>
using namespace std;

void funcRec(int u, char v);

int main()
{
funcRec(5,'A');
}

void funcRec(int u, char v)
{
if (u == 0)
cout << v;
else if (u == 1)
cout << static_cast<char>(static_cast<int>(v)+1);
else
funcRec(u-1,v);
}

Output: 

Recursion Chapter 17 > Q.7

Q7:

#include <iostream>

using namespace std;

int mystery(int number);

int main()

{

while (1)

{

int x;

cout << "x: ";

cin >> x;

cout << mystery(x) << endl << endl;

}

}

int mystery(int number)

{

if (number == 0)

return number;

else

return (number + mystery(number-1));

}

Output: