From b88bf1e6b60fe621824b39f77c140952ea8d7c07 Mon Sep 17 00:00:00 2001
From: Evan Ferrao <evanferrao@gmail.com>
Date: Fri, 9 Aug 2024 23:42:01 +0530
Subject: [PATCH] mynotes: day4: recursion hell

---
 Recursion/Fibonacci.java                  | 25 +++++++++++++++++++++
 Recursion/PrintMtoN.java                  | 27 +++++++++++++++++++++++
 Recursion/PrintMtoNUsingBacktracking.java | 27 +++++++++++++++++++++++
 Recursion/PrintNtoM.java                  | 27 +++++++++++++++++++++++
 Recursion/PrintNtoMUsingBacktracking.java | 21 ++++++++++++++++++
 5 files changed, 127 insertions(+)
 create mode 100644 Recursion/Fibonacci.java
 create mode 100644 Recursion/PrintMtoN.java
 create mode 100644 Recursion/PrintMtoNUsingBacktracking.java
 create mode 100644 Recursion/PrintNtoM.java
 create mode 100644 Recursion/PrintNtoMUsingBacktracking.java

diff --git a/Recursion/Fibonacci.java b/Recursion/Fibonacci.java
new file mode 100644
index 0000000..cbb25bc
--- /dev/null
+++ b/Recursion/Fibonacci.java
@@ -0,0 +1,25 @@
+// write code to find the nth fibonacci number using recursion
+import java.util.Scanner;
+public class Fibonacci{
+    static int first=0,second=1,next=0;
+    static void printFibonacci(int count){
+        if(count>0){
+            next = first + second;
+            first = second;
+            second = next;
+            System.out.print(" "+next);
+            printFibonacci(count-1);
+
+            // can you assign proper variable names to n1, n2 and n3?
+            // n1 should be named as first, n2 as second and n3 as next
+        }
+    }
+    public static void main(String args[]){
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter the number of terms: ");
+        int count = sc.nextInt();
+        System.out.print(first+" "+second);//printing 0 and 1
+        printFibonacci(count-2);//n-2 because 2 numbers are already printed
+        sc.close();
+    }
+}
\ No newline at end of file
diff --git a/Recursion/PrintMtoN.java b/Recursion/PrintMtoN.java
new file mode 100644
index 0000000..0c17950
--- /dev/null
+++ b/Recursion/PrintMtoN.java
@@ -0,0 +1,27 @@
+import java.util.Scanner;
+
+class PrintMtoN {
+    
+    static void func(int i, int n){
+        
+            // Base Condition.
+            if(i<n) return;
+            System.out.println(i);
+
+            // Function call to print i till i decrements to 1.
+            func(i-1,n);
+
+    }
+    public static void main(String[] args) {
+
+       // Here, let’s take the value of n to be 4.
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter the value of m (Ending Variable): ");
+        int m = sc.nextInt();
+        System.out.println("Enter the value of n (Starting Variable): ");
+        int n = sc.nextInt();
+        //int n = 8;
+        func(m,n);
+        sc.close();
+    }
+}
\ No newline at end of file
diff --git a/Recursion/PrintMtoNUsingBacktracking.java b/Recursion/PrintMtoNUsingBacktracking.java
new file mode 100644
index 0000000..d56df36
--- /dev/null
+++ b/Recursion/PrintMtoNUsingBacktracking.java
@@ -0,0 +1,27 @@
+import java.util.Scanner;
+
+class PrintMtoNUsingBacktracking {
+    
+    static void func(int i, int n){
+        
+            // Base Condition.
+            if(i>n) return;
+            
+            // Function call to print(i+1) integers.
+            func(i+1,n);
+            System.out.println(i);
+
+    }
+    public static void main(String[] args) {
+
+       // Here, let’s take the value of n to be 4.
+       //int n = 8;
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter the value of m (Ending Variable): ");
+        int m = sc.nextInt();
+        System.out.println("Enter the value of n (Starting Variable): ");
+        int n = sc.nextInt();
+        func(n,m);
+        sc.close();
+    }
+}
\ No newline at end of file
diff --git a/Recursion/PrintNtoM.java b/Recursion/PrintNtoM.java
new file mode 100644
index 0000000..61542c0
--- /dev/null
+++ b/Recursion/PrintNtoM.java
@@ -0,0 +1,27 @@
+// write a code to print N to one using recursion and function in java using backtracking
+import java.util.Scanner;
+class PrintNtoMUsingBacktracking {
+    
+    static void func(int i, int n){
+        
+            // Base Condition.
+            if(i<n) return;
+            
+            // Function call to print(n-1) integers.
+            func(i-1,n);
+            System.out.println(i);
+
+    }
+    public static void main(String[] args) {
+
+       // Here, let’s take the value of n to be 4.
+        System.out.println("Enter the value of n (Starting Variable): ");
+        Scanner sc = new Scanner(System.in);
+        int n = sc.nextInt();
+        System.out.println("Enter the value of m (Ending Variable): ");
+        int m = sc.nextInt();
+        //int n = 8;
+        func(m,n);
+        sc.close();
+    }
+}
\ No newline at end of file
diff --git a/Recursion/PrintNtoMUsingBacktracking.java b/Recursion/PrintNtoMUsingBacktracking.java
new file mode 100644
index 0000000..92e1ea5
--- /dev/null
+++ b/Recursion/PrintNtoMUsingBacktracking.java
@@ -0,0 +1,21 @@
+// write a code to print N to one using recursion and function in java using backtracking
+
+class PrintNtoMUsingBacktracking {
+    
+    static void func(int i, int n){
+        
+            // Base Condition.
+            if(i<n) return;
+            
+            // Function call to print(n-1) integers.
+            func(i-1,n);
+            System.out.println(i);
+
+    }
+    public static void main(String[] args) {
+
+       // Here, let’s take the value of n to be 4.
+       int n = 8;
+       func(n,4);
+    }
+}
\ No newline at end of file