Tetranacci Numbers | A space optimized based Java program to print the nth tetranacci number ; Function to print the N - th tetranacci number ; Initialize first four numbers to base cases ; declare a current variable ; Loop to add previous four numbers for each number starting from 4 and then assign first , second , third to second , third , fourth and curr to fourth respectively ; Driver code
import java . io . * ; import java . util . * ; import java . lang . * ; class GFG { static void printTetra ( int n ) { if ( n < 0 ) return ; int first = 0 , second = 1 ; int third = 1 , fourth = 2 ; int curr = 0 ; if ( n == 0 ) System . out . print ( first ) ; else if ( n == 1 n == 2 ) System . out . print ( second ) ; else if ( n == 3 ) System . out . print ( fourth ) ; else { for ( int i = 4 ; i <= n ; i ++ ) { curr = first + second + third + fourth ; first = second ; second = third ; third = fourth ; fourth = curr ; } System . out . print ( curr ) ; } } public static void main ( String [ ] args ) { int n = 10 ; printTetra ( n ) ; } }