Find sum of modulo K of first N natural number | Java program to find sum of modulo K of first N natural numbers . ; Return sum of modulo K of first N natural numbers . ; Counting the number of times 1 , 2 , . . , K - 1 , 0 sequence occurs . ; Finding the number of elements left which are incomplete of sequence Leads to Case 1 type . ; adding multiplication of number of times 1 , 2 , . . , K - 1 , 0 sequence occurs and sum of first k natural number and sequence from case 1. ; Driver program
import java . io . * ; class GFG { static int findSum ( int N , int K ) { int ans = 0 ; int y = N / K ; int x = N % K ; ans = ( K * ( K - 1 ) / 2 ) * y + ( x * ( x + 1 ) ) / 2 ; return ans ; } static public void main ( String [ ] args ) { int N = 10 , K = 2 ; System . out . println ( findSum ( N , K ) ) ; } }