Recursive function is a function that calls itself, either directly or indirectly. Below are some of the examples of recursive functions, written in Java, that are beneficial for the ISC students.
Finding the Factorial
public long fact(long n){
if(n <= 1)
return 1L;
else
return n * fact(n - 1);
}
Sum of the Digits
public int sum(int n){
if(n < 10)
return n;
else
return n % 10 + sum(n / 10);
}
Count the number of digits
public int count(int n){
if(n < 10)
return 1;
else
return 1 + count(n / 10);
}
Finding GCD
public int gcd(int p, int q){
if(q == 0)
return p;
else
return gcd(q, p % q);
}
Finding ab
public int power(int a, int b){
if(b == 0)
return 1;
else if(b == 1)
return a;
else
return a * power(a, b - 1);
}
Generating Factorial Terms
public long fact(int n){
if(n == 1)
return 0;
else if(n == 2)
return 1;
else
return fact(n - 1) + fact(n - 2);
}
Displaying Factors of a Number
public static void factors(int num, int f){
if(num == f)
System.out.println(f);
else if(num % f == 0){
System.out.println(f);
factors(num, f + 1);
}
else
factors(num, f + 1);
}