NitishDiwakar

#include<iostream>
#include<cmath>

using namespace std;

int main()
{
	//-------defining variables and initializing them-------------    
	double num1, num2;
	char operation, redo;

NitishDiwakar

#include<stdio.h>
int main()
{
	// declare three variables.
	int a = 0, b = 0, sum = 0;
	printf("Please enter a number: \n" );
	// read first variable
	scanf("%d", &a);
	printf("Please enter second number: \n" );
	// read second variable

NitishDiwakar

#include <stdio.h>
int main()
{
	printf("Hello World!\n");
	return 0;
}