53 lines
1.0 KiB
Java
53 lines
1.0 KiB
Java
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package com.dsa;
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/*
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Description: To print from 1 to N and N to 1 using recursion
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Time Complexity: O(n)
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*/
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public class PrintN {
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//main starts
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public static void main(String[] args) {
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System.out.println("Printing 1 to N:");
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print2(5);
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System.out.println();
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System.out.println("Printing N to 1");
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print1(5);
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}
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//for Printing 1 to N
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static void print2(int n) {
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//base case
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if (n == 0) {
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return;
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}
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//recursive function call
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print2(n - 1);
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//print the value of n at each recursive function call
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System.out.print(n + " ");
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}
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//for Printing N to 1
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static void print1(int n) {
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//base case
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if (n == 0) {
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return;
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}
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//print the value of n first
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System.out.print(n + " ");
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//then make the recursive function call
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print1(n - 1);
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}
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/*
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Output:
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Printing 1 to N:
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1 2 3 4 5
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Printing N to 1
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5 4 3 2 1
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*/
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}
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