DSA

Stacks , Queue , LinkedList , Trees , Graphs 

Dynamic programming ,Greedy approach, searching algorithm, Sorting algorithms

import java.util.*;
class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Try programiz.pro");
        Scanner scan=new Scanner(System.in);
        int n=scan.nextInt();
        
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                System.out.print("*");
            }
            System.out.println();
        }
        //i=0 j=0 to 4
        //i=1 j=0 to 4
        
    }
}
======================================
$****   i=0 j=0
*$***  i=1 and j=1
**$**  i=2 and j=2
***$*
****$
==============
import java.util.*;
class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Try programiz.pro");
        Scanner scan=new Scanner(System.in);
        int n=scan.nextInt();
        
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                if(i==j)
                System.out.print("$");
                else
                System.out.print("*");
            }
            System.out.println();
        }
        //i=0 j=0 to 4
        //i=1 j=0 to 4
        
    }
}
============================================
$***$    i=0 j=4  i+j=n-1
*$*$*    i=1 j=3  i+j=n-1
**$**    i=2 j=2
*$*$*
$***$
=======================
import java.util.*;
class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Try programiz.pro");
        Scanner scan=new Scanner(System.in);
        int n=scan.nextInt();
        
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                if(i==j || i+j==n-1)
                System.out.print("$");
                else
                System.out.print("*");
            }
            System.out.println();
        }
        //i=0 j=0 to 4
        //i=1 j=0 to 4
        
    }
}
=====================================
*
**
***
****
*****
=================================
inside loop iterations are not constant

for(int i=0;i<n;i++)
{
  for(int j=0;j<=i;j++)
  {
  }
}

i=0 j=0 (1 itera)
i=1 j=0,1 (2 iterations)
i=2 j=0,1,2 (3 iterations)
================================
import java.util.*;
class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Try programiz.pro");
        Scanner scan=new Scanner(System.in);
        int n=scan.nextInt();
        
        for(int i=0;i<n;i++){
            for(int j=0;j<=i;j++){
               System.out.print("*");
            }
            System.out.println();
        }
        //i=0 j=0 to 4
        //i=1 j=0 to 4
        
    }
}
============================================
    *
   **
  ***
 ****
*****
======================
++j
j++

j=7
int x=++j;
sop(x)
===========