Pattern 1

import java.io.*;
class Patterns1{
public static void main(String args[])throws IOException{
//declare all the variables at the beginning
int n,i,j;
    BufferedReader br = new BufferedReader( 
                new InputStreamReader(System.in));
    System.out.println("Enter the number of rows : ");
    n = Integer.parseInt(br.readLine());
    //loop to generate the number of terms in the series
    for(i = 1; i <= n; i++){
      for(j = 1; j <= i; j++){
         System.out.print(j+" ");
        }//end of inner loop
      System.out.println();
    }//end of outer loop
  }//end of main
}//end of class