Find increasing triplets such that sum is less than or equals to k

Code :

# include <stdio.h>

void find3Numbers(int A[], int arr_size, int sum)

{

    int l, r;

    for (int i = 0; i < arr_size-2; i++){

       for (int j = i+1; j < arr_size-1; j++){         

           for (int k = j+1; k < arr_size; k++){

               if (A[i] + A[j] + A[k] <= sum)

                 printf("Triplet is %d, %d, %d\n", A[i], A[j], A[k]);

            }

        }

     }

}

int main()

{

    int A[] = {1, 2, 3, 4, 6};

    int sum = 8;

    int arr_size = sizeof(A)/sizeof(A[0]);

    find3Numbers(A, arr_size, sum);

    return 0;

}

Output :

Triplet is 1, 2, 3

Triplet is 1, 2, 4

Triplet is 1, 3, 4

Execution :

arr_size = 5

Step:1   i=0 and i<3 (arr_size-2)

                                j=1 and j<4 (arr_size-1)

                                                k=2 and k<5 (arr_size)

                                                                A[0]+A[1]+A[2]<=sum --> 1+2+3 <=8 --> 6<=8 ( true )

                                                k=3 and k<5

                                                                A[0]+A[1]+A[3]<=sum --> 1+2+4 <=8 --> 7<=8 ( true )

                                                k=4 and k<5

                                                                A[0]+A[1]+A[4]<=sum --> 1+2+6 <=8 --> 9<=8 ( false )

                                j=2 and j<4

                                                k=3 and k<5

                                                                A[0]+A[2]+A[3]<=sum --> 1+3+4 <=8 --> 8<=8 ( true )

                                                k=4 and k<5

                                                                A[0]+A[2]+A[4]<=sum --> 1+3+6 <=8 --> 10<=8 ( false )

                                j=3 and j<4

                                                k=4 and k<5

                                                                A[0]+A[3]+A[4]<=sum --> 1+4+6 <=8 --> 11<=8 ( false )

                                j=4 and j<4 (false)

Step:2  i=1 and i<3

                                j=2 and j<4

                                                k=3 and k<5

                                                                A[1]+A[2]+A[3]<=sum --> 2+3+4 <=8 --> 9<=8 ( false )

                                                k=4 and k<5

                                                                A[1]+A[2]+A[4]<=sum --> 2+3+6 <=8 --> 11<=8 ( false )

                                j=3 and j<4

                                                k=4 and k<5

                                                                A[1]+A[3]+A[4]<=sum --> 2+4+6 <=8 --> 12<=8 ( false )

                                j=4 and j<4 (false)

Step:3 i=2 and i<3

                                j=3 and j<4

                                                k=4 and k<5

                                                                A[2]+A[3]+A[4]<=sum --> 3+4+6 <=8 --> 13<=8 ( false )

                                j=4 and j<4 (false)

Step:4 i=3 and i<3 (false)

Types of variables in java

1) Local Variable - A variable which is declared inside the method is called local variable.
2) Instance Variable - A variable which is declared inside the class but outside the method, is called instance variable . It is not declared as static.
3) Static variable - A variable that is declared as static is called static variable. It cannot be local.

Example:
class A{
int data=50;//instance variable
static int m=100;//static variable
void method(){
int n=90;//local variable
}
}//end of class

Why java main method is public static void main(String []args)?

Pubilc - The main method must be public so it can be found by the JVM when the class is loaded.

Static - Since it is static it can be directly invoked via the class. Similarly, we use staticsometime for user defined methods so that we need not to make objects.

Void - void indicates that the main() method being declared does not return a value.

String []args - String is the class which can able to store collection of  characters and strings. []args refers the array of object which can store command line arguments when the program is executed with command line arguments.

For example,

java MyProgram one two

Then args contains: [ "one", "two" ]

public static void main(String [] args) {
    String one = args[0]; //=="one"
    String two = args[1]; //=="two"
}