Simple if – else statement in C

Simple if – else Syntax
The form of an if statement is as follows:

Note that every operator in C++ must return some value. For example, + operator returns sum of two numbers, * operator return multiplication of two numbers etc.
Practice Programs

(i)	   
#include<stdio.h>

void main()
{
	int x = 5;
	
	if(x)
	printf("Stephen Hawking");
	else
	printf("Albert Einstein");
}

(ii)
#include<stdio.h>

void main()
{
	int x = 5;
	
	if(x>10)
	printf("Stephen Hawking");
	else
	printf("Albert Einstein");
}

(iii)
#include<stdio.h>

void main()
{
	int x = 5;
	
	if(x == 10)
	printf("Stephen Hawking");
	else
	printf("Albert Einstein");
}

(iv)
#include<stdio.h>

void main()
{
	int x = 5, y = 10;
	
	if(x+y)
	printf("Stephen Hawking");
	else
	printf("Albert Einstein");
}

(v)
#include<stdio.h>

void main()
{
	int x = 5, y = 10;
	
	if( (x+y)>30 )
	printf("Stephen Hawking");
	else
	printf("Albert Einstein");
}

(vi)
#include<stdio.h>

void main()
{
	int x = 5, y = 10;
	
	if( (x+y)>30 )
	{
		printf("Stephen Hawking\n");
		printf("Cosmology");
	}
	
	else
	{
		printf("Albert Einstein\n");
		printf("Physics");
	}
}

(vii)
#include<stdio.h>

void main()
{
	int x = 5, y = 10;
	
	if( (x+y)>30 )
		printf("Stephen Hawking\n");
		printf("Cosmology");
	
	else
		printf("Albert Einstein\n");
		printf("Physics");
}

(viii) Testing for Leap year
#include<stdio.h>

void main()
{
	int year;
	printf("enter year \n");
	scanf("%d", &year);
	
	if((year%400==0)||((year%4==0)&&(year%100!=0)))
		printf("given year is leap year \n");	
	else
		printf("not leap year \n");
}